Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment in retained earnings, net of tax	$ 55
Income tax benefits	10,549	$ 8,788
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment in retained earnings, net of tax	(95)
Additional Paid-in-Capital [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect adjustment in retained earnings, net of tax	150
Income tax benefits	$ 209