Income Taxes, Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate Reconciliation [Abstract]
U.S. federal corporate statutory rate	21.00%	35.00%	35.00%
State and local taxes, less federal tax benefit	0.30%	3.10%	4.00%
U.S. deferred change due to U.S. tax law change	4.30%	79.50%	0.00%
Net effects of foreign tax rate differential	2.20%	6.20%	19.90%
Sale of subsidiary	0.30%	(4.60%)	(17.10%)
Repatriation cost	(0.50%)	3.80%	4.40%
U.S. transition tax toll charge net of FTC	(3.70%)	(56.20%)	0.00%
Global Intangible Low-Tax Income ("GILTI")	3.40%	0.00%	0.00%
ASC 740-30 (formerly APB 23)	(1.00%)	61.20%	26.30%
Valuation allowance changes	(1.20%)	(1.10%)	(15.90%)
Impairment of other intangible assets	0.00%	0.00%	(0.60%)
Uncertain tax positions	0.10%	1.90%	(7.00%)
Nondeductible equity compensation	(3.00%)	(9.20%)	(0.00%)
Nondeductible foreign interest expense	1.70%	(3.00%)	0.00%
Other, net	(1.00%)	(0.30%)	1.50%
Effective income tax rate	22.90%	116.30%	50.50%