Income Taxes - Provision (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income before income taxes	$ 65,326	$ 66,572
Income tax provision	24,299	24,686
CONSOLIDATED NET INCOME	$ 41,027	$ 41,886
Income tax provision as a percentage of income before income taxes	37.20%	37.10%