Income Taxes (Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income tax provision at the statutory rate	$ 55,089	$ 42,669	$ 43,768
State income taxes, net of federal benefit	4,873	4,559	4,674
Permanent difference – non deductible items	1,814	1,718	1,608
Other	(1,573)	1,545	1,507
Total	$ 60,203	$ 50,491	$ 51,557