| **Intangible Assets and Goodwill (Tables)**                                                | 12 Months Ended                                                                                                                                                                                                                                                                                                                     |
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| **Intangible Assets [Abstract]**                                                           |                                                                                                                                                                                                                                                                                                                                |
| Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block]      |    2012 2011 Software license fees$ 35,416  30,392 Customer relationships  3,036  4,435 Right-of-way  783  783    39,235  35,610 Less accumulated amortization  22,675  19,775 Net other intangible assets$ 16,560  15,835 |
| ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock                                        |  Balance at December 31, 2010$ 17,717 Asset additions  4,157 Less amortization expense  6,039 Balance at December 31, 2011  15,835 Asset additions  5,952 Less amortization expense  5,227 Balance at December 31, 2012$ 16,560                     |
| Schedule Of Amortization Expense [Table Text Block]                                        |    Years Ended December 31,   201220112010 Amortization expense$ 5,227 6,039 6,360                                                                                                                                                                                                               |
| Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] |  Years Ending December 31,   2013$ 5,098 2014  4,242 2015  3,090 2016  1,473 2017  582                                                                                                                                                                                  |

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| - Definition
Tabular disclosure of amortization expense.
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| - Definition
Tabular disclosure of the characteristics, including initial carrying value, residual amount, weighted average useful life, of finite-lived intangible assets acquired during the period by major class. A major class is composed of intangible assets that can be grouped together because they are similar, either by nature or by their use in the operations of the company.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16265-109275Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 142 -Paragraph 44 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.
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| - Definition
Tabular disclosure of the amount of amortization expense expected to be recorded in succeeding fiscal years for finite-lived intangible assets.
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| - Definition
Tabular disclosure of assets, excluding financial assets and goodwill, lacking physical substance with a finite life, by either major class or business segment.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16265-109275
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