Notes Payable and Line of Credit - Summary of Notes Payable (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Notes payable	$ 330,658	$ 330,604
Less: current portion	(188)	(258)
Notes payable, net of current portion	330,470	330,346
Senior Secured Notes with Discount
Debt Instrument [Line Items]
Notes payable	222,778	222,504
Senior Secured Notes With Premium
Debt Instrument [Line Items]
Notes payable	104,116	104,642
Ford Credit
Debt Instrument [Line Items]
Notes payable	23	28
GMAC June 2015
Debt Instrument [Line Items]
Notes payable	7	10
GMAC August 2015
Debt Instrument [Line Items]
Notes payable	8	12
Commerce Bank
Debt Instrument [Line Items]
Notes payable	3,726
American United Life Insurance
Debt Instrument [Line Items]
Notes payable		$ 3,408

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

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+ Details

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph 19, 20, 22

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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