Income Taxes (Income Tax Provisions) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Examination [Line Items]
Federal income tax expense computed on income at statutory rate	$ 32,984	$ 23,243	$ 52,243
Difference due to:
State taxes, net of federal benefit	1,041	3,059	597
Permanent tax differences	(1,405)	(682)	(2,562)
Other	1,411	748	726
Total income tax expense	$ 34,031	$ 26,368	$ 51,004
Effective income tax rate	21.70%	23.80%	34.20%