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

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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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Fair value portion of notes payable.

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-SubTopic 10
-Section S99
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Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Mar. 20, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Senior Notes	$ 248,800	$ 248,100
Unamortized debt issuance costs	1,166	1,858
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Senior Notes	$ 250,000	$ 250,300
Senior Notes [Member] \| 9½% Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Interest rate of senior notes			9.50%