Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details 7) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Reconciliation of the unrecognized tax benefits
Unrecognized tax benefits, beginning balance	$ 7,306	$ 12,347
Increase related to current year tax positions	55	0
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	(36)
(Decrease) increase related to prior year tax positions		1,290
Decrease related to lapse in statute of limitation	(1,076)	0
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	(46)	(6,331)
Unrecognized tax benefits, ending balance	$ 6,203	$ 7,306

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.

+ References

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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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