Debt Obligations (Outstanding Unsecured Notes in Series of Transactions) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of principal payments of debt obligations
Principal	$ 376,174us-gaap_ExtinguishmentOfDebtAmount	$ 29,250us-gaap_ExtinguishmentOfDebtAmount	$ 164,968us-gaap_ExtinguishmentOfDebtAmount
Repurchase Amount	383,768us-gaap_EarlyRepaymentOfSeniorDebt	31,369us-gaap_EarlyRepaymentOfSeniorDebt	338,097us-gaap_EarlyRepaymentOfSeniorDebt
Gain (Loss) on Early Extinguishment of Debt	(7,594)	(2,119)	(22,002)
Acceleration of Deferred Financing Amortization	152	40	451
Note Three [Member]
Schedule of principal payments of debt obligations
Principal			301
Repurchase Amount			303
Gain (Loss) on Early Extinguishment of Debt			(2)
Acceleration of Deferred Financing Amortization			0
Note Four [Member]
Schedule of principal payments of debt obligations
Principal	218,549	19,830	4,302
Repurchase Amount	219,404	20,853	4,566
Gain (Loss) on Early Extinguishment of Debt	(855)	(1,020)	(264)
Acceleration of Deferred Financing Amortization	9	16	8
Note Five [Member]
Schedule of principal payments of debt obligations
Principal	157,625	8,910	60,794
Repurchase Amount	164,364	9,945	69,497
Gain (Loss) on Early Extinguishment of Debt	(6,739)	(1,036)	(8,712)
Acceleration of Deferred Financing Amortization	143	23	183
Note Six [Member]
Schedule of principal payments of debt obligations
Principal		510	99,571
Repurchase Amount		571	112,541
Gain (Loss) on Early Extinguishment of Debt		(63)	(13,024)
Acceleration of Deferred Financing Amortization		1	260
Discharge of Debt [Member]
Schedule of principal payments of debt obligations
Repurchase Amount	$ 383,768	$ 31,369	$ 186,907

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

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Gross amount of debt extinguished.

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Reflects the difference between the fair value of payments made to legally extinguish a debt and its carrying value at that time. This item excludes the write-off of amounts previously capitalized as debt issuance costs.

+ References

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

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-SubTopic 50

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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