Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Outstanding debt	$ 368,382	$ 399,928
Partner Synthetic Participations [Member]
Debt Instrument [Line Items]
Outstanding debt	5,024	1,199
Funding Debt [Member]
Debt Instrument [Line Items]
Outstanding debt	$ 368,382	387,928
ODAST Agreement Due May 2018 [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Fixed interest rate	3.40%
Outstanding debt	$ 174,976	174,972
ODART Agreement Due September 2016 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Variable interest rate	3.70%
Outstanding debt	$ 86,732	105,598
ODAC Agreement Due May 2017 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Variable interest rate	8.40%
Outstanding debt	$ 18,782	32,733
ODAP Agreement Due August 2016 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Variable interest rate	5.00%
Outstanding debt	$ 22,727	56,686
PORT Agreement Due June 2017 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Variable interest rate	2.40%
Outstanding debt	$ 15,011	0
RAOD Agreement Due May 2017 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Variable interest rate	3.20%
Outstanding debt	$ 28,209	0
SBAF Agreement Due July 2015 through May 2017 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Fixed interest rate	7.40%
Outstanding debt	$ 16,921	16,740
Corporate Debt [Member]
Debt Instrument [Line Items]
Outstanding debt	$ 0	12,000
Corporate Debt [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Variable interest rate	4.50%
Outstanding debt	$ 0	$ 12,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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