Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Feb. 28, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Amount of variable rate loans hedged using interest rate swaps	$ 980,000		$ 980,000
Amount hedged of borrowed funds using forward starting interest rate swaps	980,000		980,000		$ 415,000
Amount to be hedged of borrowed funds using forward starting interest rate swaps	$ 565,000		$ 565,000
Weighted-average interest rate to be paid	1.96%		1.96%
Interest rate cash flow hedge loss to be reclassified during next 12 months, net	$ 581		$ 581
Capital market products income	$ 2,592	$ 2,916	$ 6,185	$ 8,197
Portion of fair value of outstanding interest rate swaps covered by collateral agreements (percent)	100.00%		100.00%			100.00%