Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details 7) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Reconciliation of the unrecognized tax benefits
Unrecognized tax benefits, beginning balance	$ 3,649	$ 4,670
Increase related to current year tax positions	2,834	55
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	(10)
(Decrease) increase related to prior year tax positions		46
Decrease related to lapse in statute of limitation	(1,457)	(1,076)
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	0	(46)
Unrecognized tax benefits, ending balance	$ 5,016	$ 3,649

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount of unrecognized tax benefits.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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