Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Abstract]
Reduction in value of goodwill	$ 668,900	$ 251,826
Effect on permanent book-tax basis difference	548,800
Effect on book-tax temporary basis difference	102,000
Goodwill impairment, amortization expense	$ 18,000
U.S. Federal income tax rate	21.00%	35.00%
U.S. Tax Reform			$ 39,603
Net operating loss carryforwards	$ 210,000
Limitation on operating loss carryforward usage as percent of taxable income	80.00%
Deferred tax assets, various state	$ 19,600
Foreign tax credit carryforward	54,500
Unrecognized tax benefits	13,206	$ 30,558	30,656	$ 29,956
Interest and penalties accrued	5,000	$ 9,700	$ 9,700
Reduction to unrecognized tax benefits, foreign tax audits	19,852
Increase in valuation allowance	$ 61,900