Income Taxes (Detail Textuals) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income tax expense	$ 15,753	$ 10,867	$ 44,720	$ 32,384
Income tax effective tax rate	37.80%	37.80%	37.80%	37.80%
Valuation allowance on deferred tax assets	$ 4,710	$ 4,280	$ 4,710	$ 4,280
Valuation allowance related to specific state income tax credits				$ 4,710
Net deferred tax asset realized based upon future taxable income	156,000		156,000
Unrecognized income tax benefits	$ 3,790		$ 3,790		$ 3,980