Income Taxes Income Tax Contingency (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at January 1,	$ 10,124	$ 8,557	$ 9,964
Tax positions, current period	543	3,472	983
Tax positions, prior period	(304)
Tax positions, prior period		180	83
Settlements with taxing authorities	(2,207)	(1,154)	(1,657)
Lapse of applicable statute of limitations	(685)	(931)	(816)
Unrecognized tax benefits at December 31,	$ 7,471	$ 10,124	$ 8,557

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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