Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Statement of Stockholders' Equity [Abstract]
Tax effect from new accounting principle adoption	$ 83
Tax effect from share-based compensation	726
Tax effect from tax receivable agreement	$ 50	$ 1,845

Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration