Income Taxes (Effective Income Tax Rate Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Tax provision at statutory rate based on income before income taxes (percent)	21.00%	21.00%	35.00%
Effective Income Tax Rate Reconciliation Tax Reform, Domestic	0.00%	1.80%	(111.00%)
Effective Income Tax Rate Reconciliation Tax Reform, International	0.00%	(3.60%)	0.00%
Effective Income Tax Rate Reconciliation, Consolidated Group Restructuring	0.00%	0.00%	(7.40%)
Foreign income taxes (percent)	6.40%	3.60%	(5.30%)
Federal research credit (percent)	(4.00%)	(2.80%)	(2.80%)
Effective Income Tax Rate Reconciliation, Tax treaty protocols, Percent	(2.90%)	0.00%	0.00%
Settlement of taxing authority examinations (percent)	(7.70%)	(0.70%)	(2.10%)
Stock-based compensation (percent)	(15.40%)	(1.60%)	(2.10%)
Non deductible/non-taxable items (percent)	2.80%	(1.40%)	(1.00%)
State income taxes, net of federal tax benefit (percent)	0.30%	1.60%	2.80%
Effective Income Tax Rate Reconciliation, US tax on worldwide earnings at different rates, Percent	7.90%	2.90%	0.00%
Other, net (percent)	(0.10%)	(1.50%)	0.80%
Effective income tax rate, continuing operations (percent)	8.30%	19.30%	(93.10%)