Notes Payable and Line of Credit - Summary of Notes Payable (Parenthetical) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2014	Dec. 31, 2013
Senior Secured Notes with Discount
Debt Instrument [Line Items]
Debt instrument, maturity date	Jul. 01, 2018
Senior secured notes, discount	$ 2,222	$ 2,496
Debt instrument, interest rate	12.125%
Senior Secured Notes With Premium
Debt Instrument [Line Items]
Debt instrument, maturity date	Jul. 01, 2018
Debt instrument, interest rate	12.125%
Senior secured notes, premium	4,116	4,642
Ford Credit
Debt Instrument [Line Items]
Debt instrument, interest rate	6.60%
Notes payable periodic installment amount	1
GMAC June 2015
Debt Instrument [Line Items]
Debt instrument, interest rate	2.96%
Notes payable periodic installment amount	1
GMAC August 2015
Debt Instrument [Line Items]
Debt instrument, interest rate	2.96%
Notes payable periodic installment amount	$ 1

Contractual interest rate for funds borrowed, under the debt agreement.

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- Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

+ Details

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Balance Type:	debit
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- Definition

The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

+ Details

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