| **Commitments and Contingencies (Tables)**                                  | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
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| **Commitments and Contingencies [Abstract]**                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Schedule Of Future Minimum Lease Payments                                   |  Years ending December 31: Operating Capital 2013$ 27,764  11,775 2014  23,809  11,784 2015  22,527  11,794 2016  19,600  11,804 2017  15,411  11,783 2018 and thereafter  64,944  54,948 Total minimum lease payments$ 174,055  113,888 Less amount representing interest    33,276 Less current maturity of obligations under capital leases    5,995 Long-term obligations under capital leases, excluding  current maturity  $ 74,617 |
| Schedule Of Operating Lease Receivables Minimum Payments [Table Text Block] |  Years ending December 31,   2013$11,322 2014 6,325 2015 5,094 2016 4,969 2017 4,949 2018 and thereafter 27,064 Total minimum future service revenues$59,723                                                                                                                                                                                                                                                                                                                                                                        |

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| - Definition
No authoritative reference available.
+ References
No definition available.
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| - Definition
Tabular disclosure of future minimum lease payments as of the date of the latest balance sheet presented, in aggregate and for each of the five years succeeding fiscal years, with separate deductions from the total for the amount representing executor costs, including any profit thereon, included in the minimum lease payments and for the amount of the imputed interest necessary to reduce the net minimum lease payments to present value.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737
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