Accumulated Other Comprehensive Loss - Reclassified From AOCI (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Tax (expense) benefit	$ 9,215	$ 60,609	$ 55,956	$ 52,285
Net of tax		(862)	(862)
Loss on Cash Flow Hedge
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net of tax		(862)	(862)
Loss on Cash Flow Hedge | Interest rate contract | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense		862	862
Tax (expense) benefit		0	0
Net of tax		$ 862	$ 862