Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Taxes [Line Items]
Cumulative undistributed earnings of foreign subsidiaries				$ 928,000
Foreign earnings repatriated		$ 522,000
Income tax incentives		$ 8,247	$ 7,333
Net impact of tax incentives, per diluted share		$ 0.17	$ 0.15
Unrecognized tax benefits including interest and penalties		$ 300
Interest on unrecognized tax		47
Decreases related to prior year tax positions		$ 500
State And Local Jurisdiction [Member]
Income Taxes [Line Items]
Income tax expense on foreign earnings expected to be repatriated	$ 9,400
Foreign Country [Member]
Income Taxes [Line Items]
Income tax expense on foreign earnings expected to be repatriated	$ 30,700
China [Member]
Income Taxes [Line Items]
Income tax holidays expiration date		2018
Income tax incentives		$ 1,449	$ 888
Malaysia [Member}
Income Taxes [Line Items]
Income tax holidays expiration date		2021
Income tax incentives		$ 3,219	3,151
Thailand [Member]
Income Taxes [Line Items]
Income tax holidays expiration date		2028
Income tax incentives		$ 3,579	$ 3,294