| **Transactions with Related Parties**     | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            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| **Related Party Transactions [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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| Transactions with Related Parties         | TRANSACTIONS WITH RELATED PARTIES We have a Support Agreement with Caterpillar, which provides that Caterpillar will (1) remain, directly or indirectly, our sole owner; (2) cause us to maintain a tangible net worth of at least $20 million and (3) ensure that we maintain a ratio of profit before income taxes and interest expense to interest expense (as defined by the Support Agreement) of not less than 1.15 to 1,  calculated on an annual basis.  Although this agreement can be modified or terminated by either party, any termination or any modification which would adversely affect holders of our debt requires the consent of holders of 66-2/3 percent in principal amount of outstanding debt of each series so affected.  Any modification or termination which would adversely affect the lenders under the Credit Facility requires their consent.  Caterpillar's obligation under this agreement is not directly enforceable by any of our creditors and does not constitute a guarantee of any of our obligations.  A cash dividend of $600 million, $400 million and $200 million was paid to Caterpillar in 2015, 2014 and 2013, respectively. We have variable amount lending agreements and other notes receivable with Caterpillar.  Under these agreements, we may borrow up to $2.28 billion from Caterpillar, and Caterpillar may borrow up to $1.29 billion from us.  The agreements are in effect for indefinite periods of time and may be changed or terminated by either party with 30 days notice.  We extended a $2 billion committed credit facility to Caterpillar, which expires in February 2019.  Under this agreement, we receive a fee from Caterpillar based on amounts drawn under the credit facility and a commitment fee for the undrawn amounts under the credit facility.  Information concerning these agreements was as follows: (Millions of dollars)        2015 2014 2013Notes payable as of December 31, $1,096 $1,108 $1,118Notes receivable as of December 31, $490 $414 $345Interest expense $6 $7 $7Interest income on Notes Receivable with Caterpillar(1) $21 $18 $19Fees on committed credit facility extended to Caterpillar(1) $40 $41 $41       (1) Included in Other revenues, net in the Consolidated Statements of Profit. We have agreements with Caterpillar to purchase certain trade receivables at a discount.  Information pertaining to these purchases was as follows: (Millions of dollars)        2015 2014 2013Purchases made $33,154 $36,816 $33,018Discounts earned $222 $243 $233Balance as of December 31, $2,601 $3,238 $3,092       We participate in certain marketing programs offered in conjunction with Caterpillar that allow us to periodically offer financing to customers at interest rates that are below market rates.  Under these marketing programs, Caterpillar funds an amount at the outset of the transaction, which we then recognize as revenue over the term of the financing.  During 2015, 2014 and 2013, relative to such programs, we received $188 million, $173 million and $189 million, respectively.  We have finance receivables and equipment on operating leases, net of depreciation, with  Caterpillar wholly-owned dealers of $49 million and $58 million as of December 31, 2015 and 2014, respectively.  For the years ended December 31, 2015, 2014 and 2013, we recognized revenues of $9 million, $11 million and $11 million, respectively, related to these finance receivables and operating leases.  For the years ended December 31, 2015, 2014 and 2013, we recognized depreciation related to these operating leases of $7 million, $9 million and $9 million, respectively.  At December 31, 2015 and 2014, $418 million and $568 million, respectively, of our portfolio is subject to guarantees by Caterpillar.   We participate in various benefit plans, which are administered by Caterpillar.  These plans include employee medical plans and postretirement benefit plans.  We reimburse Caterpillar for these charges.  During 2015, 2014 and 2013, these charges amounted to $29 million, $30 million and $27 million, respectively.  Included in these charges are contributions to defined benefit plans in the amount of $7 million for each of 2015, 2014 and 2013.  These contributions are related to our participation in the following defined benefit plans that are administered by Caterpillar: the Caterpillar Inc. Retirement Income Plan, the Caterpillar Inc. Supplemental Retirement Plan and the Caterpillar Inc. Retiree Benefit Program.  The total cost of the defined benefit plans is determined by actuarial valuation and we receive an allocation of the service and prior service cost based on headcount.  We participate in the Caterpillar stock incentive plans.  In 2015, 2014 and 2013, Caterpillar allocated to us $12 million, $11 million and $11 million, respectively, in expenses related to stock based compensation.  Further information about these plans is available in Caterpillar’s 2015 Annual Report on Form 10-K filed separately with the Securities and Exchange Commission.Caterpillar provides operational and administrative support, which is integral to the conduct of our business.  In 2015, 2014 and 2013, these operational and support charges for which we reimburse Caterpillar amounted to $37 million, $37 million and $33 million, respectively.  In addition, we provide administrative support services to certain Caterpillar subsidiaries.  Caterpillar reimburses us for these charges.  During 2015, 2014 and 2013, these charges amounted to $12 million in each year.We join Caterpillar in the filing of a consolidated U.S. Federal income tax return and certain state income tax returns.  In accordance with our tax sharing agreement with Caterpillar, we generally pay to or receive from Caterpillar our allocated share of income taxes or credits reflected in these consolidated filings. This amount is calculated on a separate return basis by taking taxable income times the applicable statutory tax rate and includes payment for certain tax attributes earned during the year. |

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| - Definition
The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.
+ References
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