Related Party Transactions (Details 2) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Assets, GQM LLC	$ 152,193	$ 151,802
Liabilities, GQM LLC	(24,092)	(20,710)
Net assets, GQM LLC	$ 128,101	$ 131,092

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.

+ Details

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5710-111685

+ Details

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- Definition

The net carrying amount of the consolidated Variable Interest Entity's assets and liabilities included in the reporting entity's statement of financial position.

+ References

+ Details

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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

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