Commitments and Contingencies - Guarantees and Indemnifications (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Accrued Indemnification Obligation
Accrued indemnification obligation	$ 4,452,500	$ 4,080,500
Member of Board of Directors \| Tax indemnification
Accrued Indemnification Obligation
Accrued indemnification obligation	$ 4,452,500	$ 4,080,500

Amount of loss contingency liability expected to be resolved within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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