Income Taxes (Schedule of Effective Income Tax Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Tax at statutory rate	$ 47,015	$ 50,595	$ 44,611
Change in federal income tax rate	0	(110,508)	0
State income taxes, net of federal tax benefits	8,098	4,943	3,032
Non-deductible meals and entertainment	1,044	1,495	1,549
Income tax credits	(1,800)	(1,780)	(1,900)
Equity compensation	(312)	(820)	0
Other, net	1,688	(2,257)	1,039
Total income tax expense (benefit)	$ 55,733	$ (58,332)	$ 48,331

Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to excess tax benefit for share-based compensation cost.

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