Income Taxes (Income Tax Expense Difference) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Tax expense at Federal statutory income tax rate	$ 11,576	$ 23,224	$ 46,529
Impact of foreign operations	107	826	(9,603)
Foreign source income, net of tax credits	(2,248)	(197)	1,087
State tax, net of federal	(690)	121	279
Unrecognized tax benefits	543	(869)	2,874
U.S. Tax Reform	0	209	13,683
Equity compensation excess tax deductions	(2,902)	(2,238)	(3,867)
General business credits	(656)	(2,172)	(1,080)
Distribution related foreign taxes	1,240	1,916	2,173
Valuation allowance change (excluding U.S. Tax Reform)	(2,527)	602	1,393
Disproportionate tax effect of pension settlement charges	2,510	0	0
Other	854	1,516	(1,002)
Total	$ 7,807	$ 22,938	$ 52,466