Income Taxes Liability for Uncertain Tax Positions (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance at beginning of year	$ 3,970,000	$ 7,125,000	$ 4,197,000
Increase for tax positions related to prior years	0	0	3,970,000
Decrease for tax positions related to prior years	0	0	(1,169,000)
Decrease for expiration of statute of limitations	0	(3,155,000)	0
Increase for effects of foreign exchange rates	0	0	127,000
Balance at end of year	3,970,000	$ 3,970,000	$ 7,125,000
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 4,000,000

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Amount of unrecognized tax benefits.

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