Derivative Financial Instruments - Impact of Derivatives on Consolidated Statement of Changes in Stockholders' Equity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Amount of loss recognized in other comprehensive income	$ (27,162)	$ (5,470)	$ (35,441)	$ (5,470)
Less: amount of loss reclassified in interest expense	5,411	3,587	16,157	3,587
Total change in other comprehensive income for unrealized losses on derivatives	$ (21,751)	$ (1,883)	$ (19,284)	$ (1,883)