Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Income tax expense	$ (1,396)	$ 32,547	$ 45,080	$ 89,426
Effective tax rate	(1.00%)	23.00%	14.00%	25.00%
Federal statutory rate			21.00%
Decrease in valuation allowance	$ 25,000		$ 25,000
Tax benefit relating to uncertain tax positions	7,200		5,600
State and local income tax expense	4,100	$ 2,300	7,300	$ 6,200
Federal income tax expense				16,100
One-time rate change on deferred tax assets and liabilities				8,300
Tax benefit from foreign subsidiary earnings				$ 5,800
Foreign tax credit carry forwards	27,500		27,500
Valuation allowance	27,500		27,500
Second component of tax deductible goodwill, net of tax	$ 700		$ 700