<PAGE>   1
                                                                    EXHIBIT 10.L


                                  THE VIAD CORP

                            SUPPLEMENTAL PENSION PLAN
            (AMENDED AND RESTATED AS OF DECEMBER 1, 1999), PREVIOUSLY
        AMENDED AND RESTATED AS OF SEPTEMBER 30, 1997 AND PRIOR THERETO,
                               ON JANUARY 1, 1987

1.       PURPOSE

The purpose of the Viad Corp Supplemental Pension Plan (hereinafter referred to
as the "Plan") is to provide deferred compensation to Eligible Employees (as
defined in paragraph 2) on and after January 1, 1976. It is the intention of
Viad Corp (hereinafter called the "Company") that Eligible Employees are those
employees designated by the Company, or the Chief Executive Officer of the
Company, pursuant to paragraph 2, from a select group of management or
highly-compensated employees of the Company, or any of its subsidiaries or
affiliates (hereinafter referred to as "Subsidiaries") and that the Plan
continue to be eligible for exemptions under Parts 1, 2, 3 and 4 of Title I of
ERISA and U.S. Department of Labor regulations. It also is the intention of the
Company that the Plan be unfunded, that any Eligible Employee's rights under the
Plan are those of a general creditor only, and that there be no elections with
respect to any benefits under the Plan by Eligible Employees. Subject to rights
and benefits expressly fixed by the terms hereof, the Company also intends that
the Plan may be amended or terminated and that benefits may be reduced or
eliminated as the Board of Directors of the Company determines from time to time
and that individuals' rights may be altered.

2.       PARTICIPATION

An employee of the Company (or any of its Subsidiaries) may become eligible to
participate in the Plan (referred to herein as "Eligible Employee") when
approved by the Board of Directors of the Company (or a committee thereof), or
by the Chief Executive Officer of the Company, as specifically designated in
each Schedule of Benefits (which is attached hereto, and by this reference made
a part hereof). A list of Eligible Employees with respect to each Schedule of
Benefits is correspondingly denominated and attached as an exhibit to the Plan
(referred to herein as "Exhibit") and each such Exhibit shall be periodically
updated.

3.       FUNDING

No fund shall be established to provide for the payment of benefits under the
Plan. No trust, other than one which will not cause the Plan to be "funded"
under current Internal Revenue Service and U.S. Department of Labor regulations
and rulings, shall be created. Any rights of an Eligible Employee or any other
person claiming by or through him or her shall be those of a general


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creditor of the Company only. The Company may create book reserves or take such
other steps as it deems appropriate to provide for its expected liabilities
under the Plan.

4.       CATEGORIES OF BENEFIT PAYMENTS TO ELIGIBLE EMPLOYEES

Benefits shall be payable by the Company in accordance with the terms and
conditions of the Plan and as described in each Schedule of Benefits to the
Eligible Employees described in each such Schedule of Benefits and its
corresponding Exhibit.

5.       RETIREMENT BENEFITS

Except, as otherwise expressly provided in the Plan or in a Schedule of
Benefits, the Plan shall make monthly payments to an Eligible Employee at the
same time such Eligible Employee receives or would be deemed to receive under
any Schedule of Benefits his or her pension benefits under the pension plan(s)
sponsored by the Company, or any of its Subsidiaries, (herein, and in any
Schedule of Benefits, referred to for the purposes of the Plan as "the time of
his or her retirement"), but in no event shall monthly payments begin before
such Eligible Employee has attained the age of 55 and has actually left the
employ of the Company or its Subsidiaries. Unless otherwise expressly stated in
a Schedule of Benefits, such monthly payments shall be equal to the amount by
which the sum of the monthly pension benefits payable to the Eligible Employee
from all pension plans sponsored by the Company or any of its Subsidiaries,
other than this Plan and a plan qualified under Internal Revenue Code Section
401(k), (hereinafter called "Pension Plans"), is less than the aggregate
amount(s) determined under the applicable Schedule(s) of Benefits. In making
this determination, the amount(s) from such Pension Plan(s) shall be determined
prior to the election of any payment options (such as joint and survivor
elections) and without regard to Internal Revenue Code Section 415 or any other
law or regulation which would limit benefit amounts from such Pension Plan(s).
In addition, when an Eligible Employee is a participant in more than one Pension
Plan and benefits under any one of such Pension Plans are not available
immediately on account of early retirement eligibility provisions, then, for the
purposes of the Plan, such benefits shall be taken into account as though
payable immediately on an actuarially equivalent basis, as reasonably determined
by the Viad Retirement Committee ("Committee") in its sole discretion.

6.       FINAL AVERAGE EARNINGS

Final Average Earnings for purposes of Schedules A, B, B', C and E shall be as
defined in the Viad Corp Retirement Income Plan (hereinafter, "VCRIP") plus
amounts that were not included in Final Average Earnings because such amounts
were deferred and, for Schedules A, B, B' and C only, the average of the highest
five calendar years of Management Incentive Plan (hereinafter,


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"MIP") (or its predecessor or successor Plan) awards (whether paid or deferred)
made to him or her while in continuous service, except that for Schedules B, C,
and E, when calculating Final Average Earnings for years following December 31,
1997 only one-half of MIP (if MIP is included in the calculation of
compensation) shall be used and there shall be applied a transition benefit
calculation as more fully described in the appropriate Schedules. Any deferrals
included in Final Average Earnings by reason hereof shall only be used once in
calculating such Final Average Earnings.

7.       OPTIONAL FORMS

If any pension benefit is payable to an Eligible Employee from a Pension Plan,
and an optional form of payment is elected under that Pension Plan, then a
similar election will be deemed made under the Plan. If two or more such
pensions are payable from such other Pension Plans, then the option selected
from the Pension Plan generating the largest monthly pension payment (include
the beneficiary designation in connection with such option and benefits, if
applicable) shall prevail for the purposes of the Plan. Notwithstanding the
foregoing, no lump sum distributions shall occur to be permitted hereunder.

8.       LISTING OF ELIGIBLE EMPLOYEES

A listing of Eligible Employees shall be maintained in the form of the Exhibits
to the Plan. Exhibit A shall contain those covered under Schedule A, and so on
for B, B', C, D, and E. If an employee is incorrectly included or excluded from
an Exhibit, actual entitlement to participation and benefits under the Plan
shall be reasonably determined by the Committee in its sole discretion.

9.       SURVIVOR'S BENEFIT

If while covered by this program, for purposes other than a terminated vested
benefit, an Eligible Employee dies and if on the date of his or her death such
Eligible Employee is:

a) Covered by Schedule A, B, B', C, D or E and has 5 years of service; or

b) 55 years of age or older;

then his or her Eligible Spouse, as defined in the VCRIP shall be entitled to a
survivor's benefit. This survivor's benefit shall be calculated by assuming that
the Eligible Employee (i) was 55 years of age (or his actual age if older) on
the date of death; (ii) retired under the VCRIP on the first day of the month
following his or her death; and (iii) elected a Single Life Annuity. The
Eligible Spouse will be entitled to receive 1/2 of this benefit which shall be
further


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reduced by 1/6 of 1% for each month the Eligible Spouse is more than 60 months
younger than the Eligible Employee.

The survivor's benefit under this paragraph 9 shall be reduced by any spousal
survivor's benefit payable from any qualified defined benefit plan (other than a
Section 401(k) plan or an Employee Stock Ownership Plan) sponsored by the
Company when such benefit becomes payable, as reasonably determined by the
Committee in its sole discretion.

10.      VESTING

In addition to all the terms and conditions of the Plan, no Eligible Employee or
beneficiary shall be entitled to a benefit under the Plan unless such Eligible
Employee has actually attained fully vested status in a Pension Plan which is
qualified under Internal Revenue Code Section 401 and which is mentioned in any
Schedule of Benefits covering the Eligible Employee, as reasonably determined by
the Committee in its sole discretion. Notwithstanding any other provision
hereof, any Eligible Employee hereunder who has accumulated five years of
service with the Company and its Subsidiaries taken as a whole, ignoring breaks
in service, shall be fully vested and entitled to benefits hereunder.

11.      ADMINISTRATION, AMENDMENT, MODIFICATION, AND TERMINATION OF THE PLAN

The Board of Directors of the Company may terminate the Plan or any Schedule of
Benefits at any time. Any amounts vested under the Plan prior to any such
termination shall continue to be subject to the terms, conditions, and elections
in effect under the Plan when the Plan is terminated. The Plan may be amended at
any item or from time to time by the Board of Directors of the Company. The
Company shall have full power and authority to interpret and administer the
Plan, to promulgate rules of Plan administration, to adopt a claims procedure,
to conclusively settle any disputes as to rights or benefits arising from the
Plan, and to make such decisions or take such actions as the Company, in its
sole discretion, reasonably deems necessary or advisable to aid in the proper
administration and maintenance of the Plan.

12.      MISCELLANEOUS

The Plan, and any determination made by the Committee or the Company in
connection therewith, shall be binding upon each Eligible Employee, his or her
beneficiary or beneficiaries, heirs, executors, administrators, successors and
assigns. Notwithstanding the foregoing sentence, no benefit under the Plan may
be sold, assigned, transferred, conveyed, hypothecated, encumbered, anticipated
or otherwise disposed of, and any attempt to do so shall be void. No such
benefit payment shall be, prior to actual receipt thereof by the Eligible
Employee, or his or her beneficiary or beneficiaries, as the case may be, in any
manner subject to the debts, contracts, liabilities or engagements of such


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Eligible Employee or beneficiary(ies). The Plan shall not constitute, nor be
deemed to constitute, a contract of employment between the Company, or any of
its Subsidiaries, and any Eligible Employee, nor shall any provision hereof
restrict the right of the Company or any of its Subsidiaries to discharge any
Eligible Employee from his or her employment, with or without cause.


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                                   SCHEDULE A

The benefits payable under this Schedule of Benefits are in lieu of, not in
addition to, any other benefit provided for in this Plan, it being the intent of
the Company that (i) benefits shall be payable under this Schedule of Benefits
only if it generates the largest monthly benefits when compared to other
benefits to which the Eligible Employee is otherwise entitled under the Plan,
and (ii) benefits payable under this Schedule of Benefits shall be the only
benefits payable to an Eligible Employee under the Plan. The provisions of this
Schedule A shall not be construed to modify or limit the provisions of any other
Schedule of Benefits to the extent such other Schedule of Benefits deems certain
facts to be true for the purposes of the Plan.

Benefits may be payable under this Schedule of Benefits in respect of persons
employed by the Company who are selected by the Board of Directors for inclusion
under this Schedule of Benefits. The amount used to determine the monthly
benefit payable to any Eligible Employee under paragraph 5 of the Plan is as
follows:

         A monthly Pension calculated as though the selected person was a member
         of the VCRIP and based on the rules of that Plan applicable at the time
         of his or her retirement, except that the following Table of retirement
         benefits expressed as a percentage of Final Average Earnings shall be
         used. For purposes of this Schedule of Benefits, Final Average Earnings
         shall be as defined in paragraph 6 of the Plan.

<TABLE>
<CAPTION>
         Years of    % of           % of       Years of     % of        % of
         Service      FAE         Soc. Sec.    Service      FAE       Soc. Sec.
         -------      ---         --------     -------      ---       ---------

<S>                  <C>          <C>          <C>          <C>       <C>
            1          3             2.5          11         33         27.5
            2          6             5.0          12         36         30.0
            3          9             7.5          13         39         32.5
            4         12            10.0          14         42         35.0
            5         15            12.5          15         45         37.5
            6         18            15.0          16         48         40.0
            7         21            17.5          17         51         42.5
            8         24            20.0          18         54         45.0
            9         27            22.5          19         57         47.5
           10         30            25.0          20         60         50.0
</TABLE>

Notwithstanding the foregoing, awards under the Management Incentive Plan, shall
be counted only once for purposes of this Schedule of Benefits, but on the basis
generating the largest Final Average Earnings.


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The benefit derived from this Table of Benefits shall be payable on the later of
the first day of the month following termination of employment or the first day
of the month following the month in which the participant attains age 55. The
benefit shall not be subject to any reduction resulting from the Eligible
Employee's election to retire prior to his or her normal retirement date. If the
Eligible Employee is married on the date of his or her retirement, the benefit
shall be paid in the form of a 50% Joint Survivorship Annuity and shall not be
reduced to reflect such form of payment.

If the Eligible Employee elects any other optional form of payment under the
VCRIP then the reduction in such optional form of benefit shall be based on the
unreduced, 50% Joint & Survivor Annuity benefit.

Eligible Employees under this Schedule are listed on Exhibit A to this Plan.


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                                   SCHEDULE B

Benefits may be payable under this Schedule of Benefits in respect of persons
employed by the Company who are selected by the Chief Executive Officer of the
Company. The amount used to determine the monthly benefit payable to an Eligible
Employee under paragraph 5 of the Plan is as follows:

         A monthly pension based on the rules of the VCRIP (in effect on
         December 31, 1988) for the Eligible Employee and calculated under those
         rules for years of service up to and including December 31, 1997. For
         years of service beginning January 1, 1998, the rules of the Amendment
         to the VCRIP Appendix: Greyhound Employees' Retirement Income Plan,
         effective January 1, 1998 ("the Appendix") shall apply, except that for
         purposes of the Employee's Average Monthly Compensation, the
         calculation of Final Average Earnings as set forth in Paragraph 6 of
         the Plan shall be used. For the purposes of this Schedule of Benefits,
         the amount of normal Retirement Pension with respect to compensation
         and credited service shall be the sum of the benefit determined under
         (a) and (b) below;

         (a) The Eligible Employee's Accrued Benefit as of December 31, 1997, if
         any, determined in accordance with the terms of this section as in
         effect immediately prior to January 1, 1998, multiplied by a fraction
         (not less than one), the numerator of which is the Eligible Employee's
         current Average Monthly Compensation, and the denominator of which is
         the Eligible Employee's Average Monthly Compensation determined as of
         December 31, 1997, with such calculations being determined based on the
         definitions of "Compensation" and "Average Monthly Compensation" as set
         forth in the Appendix as of December 31, 1997.

         (b) With respect to an Eligible Employee's Credited Service determined
         with respect to periods after December 31, 1997, the monthly amount of
         such normal Retirement Pension shall be the sum of the benefit
         determined under (1) and (2) below:

                  (1) 1.15 percent of the lesser of the Eligible Employee's
                  Average Monthly Compensation or his Covered Compensation,
                  multiplied by his Credited Service for periods after 1997,
                  plus

                  (2) 1.70 percent of the excess, if any, of the Eligible
                  Employee's Average Monthly Compensation over his Covered
                  Compensation, multiplied by his Credited Service for periods
                  after 1997.


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<PAGE>   9
         A Eligible Employee's Credited Service under this paragraph (b) shall
         be limited to 30 years minus any Credited Service taken into account
         for purposes of any calculation under paragraph (a) above.


         The Benefit shall be subject to no reduction if the Eligible Employee
         retires on or following his or her 60th birthday; and a reduction of
         .25% for each month his or her retirement precedes his or her 60th
         birthday. In no event, however, may an Eligible Employee retire prior
         to his or her 55th birthday. If the Eligible Employee is married on the
         date of his or her retirement, the benefit shall be paid in the form of
         a 50% Joint Survivorship Annuity and shall not be reduced to reflect
         such form of payment.

If the Eligible Employee elects any other optional form of payment under the
VCRIP the reduction in such optional form of benefits shall be based on an
unreduced, 50% Joint & Survivor Annuity benefit.

Eligible Employees under this Schedule B are listed on Exhibit B to the Plan.


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                                   SCHEDULE B'

Benefits may be payable under this Schedule of Benefits in respect of persons
employed by the Company who are selected by the Board of Directors of the
Company. For the purposes of this Schedule of Benefits, Final Average Earnings
("FAE") shall be as defined in paragraph 6 of the Plan. The amount used to
determine the monthly benefit payable to an Eligible Employee under paragraph 5
of the Plan is the greater of (1) or (2) below:

         (1)      A monthly pension based on the rules of the VCRIP (in effect
                  on December 31, 1988) for the Eligible Employee. The Benefit
                  shall be subject to no reduction if the Eligible Employee
                  retires on or following his or her 60th birthday; and a
                  reduction of .25% for each month his or her retirement
                  precedes his or her 60th birthday. In no event, however, may
                  an Eligible Employee retire prior to his or her 55th birthday.

         (2)      If the Eligible Employee is actively employed by Viad Corp at
                  such time as the Eligible Employee obtains age 58 and
                  continues to be actively employed upon the attainment of the
                  ages shown in Table A below, a monthly pension based on the
                  amount derived from Table A below, offset by the amounts in
                  Table B below.

Table A

<TABLE>
<CAPTION>
Upon attainment of       The following percentage of
the following age:       Final Average Earnings:
<S>                      <C>
       58                            30%
       59                            40%
       60                            50%
       61                            52%
       62                            54%
       63                            56%
       64                            58%
       65                            60%
</TABLE>

         The above percentages of FAE shall be attained only upon the Eligible
         Employee's birthday without any interpolation for retirements between
         birthdays.

Table B

<TABLE>
<CAPTION>
Upon retirement at      the following
The following ages:     monthly offset:
<S>                    <C>              <C>
       58                 $2,706        And all of the monthly amounts payable
       59                 $2,912        to the Eligible Employee from VCRIP and
</TABLE>


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<TABLE>
<S>                    <C>              <C>
       60                 $3,130        any and all special retirement benefits paid
       61                 $3,173        pursuant to any Change in Control
       62                 $3,216        provisions set forth in any agreements by
       63                 $3,257        and between the Eligible Employee and
       64                 $3,295        Viad Corp, (including the Executive
       65                 $3,327        Severance Agreement entered into in
                                        January of 1997) as such provisions
                                        enhance retirement benefits.
</TABLE>

In the event of a Change of Control, the Eligible Employee will receive a
retirement benefit equal to the greater of the retirement benefit calculated (a)
pursuant to the Change of Control provisions set forth in any agreements by and
between Eligible Employee and Viad Corp (including the Executive Severance
Agreement entered into in January of 1997) or (b) by using the Schedule B' as
described above.

If the Eligible Employee is married on the date of his or her retirement, the
benefit shall be paid in the form of a 50% Joint Survivorship Annuity and shall
not be reduced to reflect such form of payment.

If the Eligible Employee elects any other optional form of payment under the
VCRIP then the reduction in such optional form of benefits shall be based on an
unreduced, 50% Joint & Survivor Annuity benefit.

Eligible Employees under this Schedule B' are listed on Exhibit B' to the Plan.


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                                   SCHEDULE C

Benefits may be payable under this Schedule of Benefits in respect of persons
employed by the Company who are selected by the Chief Executive Officer of the
Company. The amount used to determine the monthly benefit payable to an Eligible
Employee under paragraph 5 of the Plan is as follows:

         A monthly pension based on the rules of the VCRIP for the Eligible
         Employee applicable at the time of his or her retirement, but subject
         to the preservation of the December 31, 1997 benefit set forth in the
         Amendment to the VCRIP Appendix: Greyhound Employees' Retirement Income
         Plan effective January 1, 1998. For the purposes of this Schedule of
         Benefits, Final Average Earnings shall be as defined in paragraph 6 of
         the Plan.

Consistent with the Amendment to the VCRIP Appendix: Greyhound Employees'
Retirement Income Plan, effective January 1, 1998, there shall be a transition
benefit calculation. The transition benefit calculation shall apply to Eligible
Employees who elect early retirement under VCRIP. The calculation compares the
(1) early retirement amount using the accrued benefit determined as of December
31, 1997 and multiplied by the applicable early retirement reduction factor in
effect as of December 31, 1997 with (2) the early retirement amount determined
by adding the accrued benefit on 12/31/97 to the accrued benefit determined
under the formula in effect on and after January 1, 1998 for years of service
after 1/1/98 and multiplied by the applicable early retirement reduction factor
in effect as of 1/1/98. The Eligible Employee shall receive the higher of the
two benefit calculations.

Eligible Employees under this Schedule C are listed on Exhibit C to the Plan.


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                                   SCHEDULE D


Benefits may be payable under this Schedule of Benefits in respect of persons
employed by the Company who are selected by the Chief Executive Officer ("CEO")
of the Company. The amount used to determine the monthly benefit payable to an
Eligible Employee under paragraph 5 of the Plan is as follows:

         A monthly pension based on the rules of the VCRIP for the Eligible
         Employee applicable at the time of his or her retirement. Final Average
         Earnings shall be as defined in paragraph 6 of the Plan, (or another
         applicable schedule of the Plan) except that 100% of the final five (or
         high five if from schedules A, B, B', or C of this Plan) MIP awards
         (whether paid or deferred) shall be considered in calculating Final
         Average Earnings.

         For purposes of this Schedule D only, Eligible Employees shall be
         defined to mean only those employees selected by the CEO who are
         eligible to receive MIP and who have reached age 55 or older on or
         before December 31, 1997.

         Coverage of an Eligible Employee under this Schedule D neither requires
         nor precludes the Eligible Employee's coverage under another Schedule
         of Benefits. However, coverage under this Schedule D also does not
         provide duplication of benefits for an Eligible Employee who, in
         addition to being covered under this Schedule D is covered under
         another Schedule of Benefits. If an Eligible Employee is covered under
         one or more Schedules, the Schedule producing the highest benefit shall
         be used to make the determination of benefits.


Eligible Employees under this Schedule D are listed on Exhibit D to the Plan.


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                                   SCHEDULE E


Employees who participate in the VCRIP and its appendices (the "Qualified Plan")
automatically become Eligible Employees under this Schedule E if their benefits
under the Qualified Plan are limited by Internal Revenue Code Section 401(a)(17)
or Section 415. The Company shall administratively identify the Eligible
Employees under this Schedule E, based on the effect of such Internal Revenue
Code provisions on their Qualified Plan benefits, and shall list them on Exhibit
E. Exhibit E shall not require separate approval of the Board of Directors or
the Chief Executive Officer of the Company.

Coverage of an Eligible Employee under this Schedule E neither requires nor
precludes the Eligible Employee's coverage under another Schedule of Benefits.
However, coverage under this Schedule E also does not provide duplication of
benefits for an Eligible Employee who, in addition to being covered under this
Schedule E, is covered under another Schedule of Benefits. The Company may
determine and communicate an Eligible Employee's aggregate benefit under this
Plan by considering this Schedule E together with any other Schedule of Benefits
that happens to cover the Eligible Employee. Subject to the foregoing, the
amount of benefit attributable to this Schedule E and payable to an Eligible
Employee pursuant to paragraph 5 of the Plan shall be determined as:

         A monthly pension based on the benefit schedule(s) and rules of the
         Qualified Plan applicable to the Eligible Employee at the time of his
         or her retirement. For purposes of this Schedule of Benefits, Final
         Average Earnings shall be as defined in the Qualified Plan (subject to
         any modifications under paragraph 6 of this Plan, if applicable) with
         respect to the Eligible Employee, and shall be determined without
         regard to the annual limit of $160,000 (as adjusted) that applied under
         the Qualified Plan pursuant to Internal Revenue Code Section
         401(a)(17). In addition, the pension computed in this manner shall not
         be reduced on account of the Internal Revenue Code Section 415
         limitations that apply under the Qualified Plan.



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