Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Net tax benefit from U.S. tax reform		$ (22,284)	$ 41,554	$ 0
Income tax expense from the Tax Act	$ 22,300
Tax benefit from income tax holiday		$ 1,900	$ 6,200	$ 5,600
Benefit from income tax holiday on diluted earnings per share (in dollars per share)		$ 0.01	$ 0.03	$ 0.02
Undistributed earnings of foreign subsidiaries	1,100,000	$ 1,100,000
Transition tax payable	$ 21,800	21,800
Income Tax Examination [Line Items]
Reductions from lapse of statutes of limitations		22	$ 17	$ 105
Foreign
Income Tax Examination [Line Items]
Repatriation of earnings estimated tax impact		91,800
Reductions from lapse of statutes of limitations		$ 2,900