Fair Value Measurement (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2012
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	$ 19,511	$ 18,839
Included in earnings as a part of:
Settlements	(22,075)	(22,247)
Ending Balance	0	0
Change in unrealized (gains) losses included in earnings for the above period for Level 3 liabilities outstanding at period-end	0	0
2019 Note Payable [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	14,777	14,180
Included in earnings as a part of:
Settlements	(16,940)	(17,112)
Ending Balance	0	0
Change in unrealized (gains) losses included in earnings for the above period for Level 3 liabilities outstanding at period-end	0	0
Interest rate swap agreement [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation:
Beginning Balance	4,734	4,659
Included in earnings as a part of:
Settlements	(5,135)	(5,135)
Ending Balance	0	0
Change in unrealized (gains) losses included in earnings for the above period for Level 3 liabilities outstanding at period-end	0	0
Net realized investment gains (losses) [Member]
Included in earnings as a part of:
Included in earnings as a part of:	401	1,245
Net realized investment gains (losses) [Member] \| 2019 Note Payable [Member]
Included in earnings as a part of:
Included in earnings as a part of:	0	769
Net realized investment gains (losses) [Member] \| Interest rate swap agreement [Member]
Included in earnings as a part of:
Included in earnings as a part of:	401	476
Loss on extinguishment of debt [Member]
Included in earnings as a part of:
Included in earnings as a part of:	2,163	2,163
Loss on extinguishment of debt [Member] \| 2019 Note Payable [Member]
Included in earnings as a part of:
Included in earnings as a part of:	2,163	2,163
Loss on extinguishment of debt [Member] \| Interest rate swap agreement [Member]
Included in earnings as a part of:
Included in earnings as a part of:	$ 0	$ 0

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Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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