Derivative Instruments and Hedging Activities - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Feb. 28, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Amount of variable rate loans hedged using interest rate swaps	$ 1,100,000
Amount hedged of borrowed funds using forward starting interest rate swaps	980,000			$ 510,000
Amount to be hedged of borrowed funds using forward starting interest rate swaps	$ 470,000
Weighted-average interest rate to be paid	1.89%
Interest rate cash flow hedge loss to be reclassified during next 12 months, net	$ 1,300
Capital market products income	$ 1,558	$ 1,376
Portion of fair value of outstanding interest rate swaps covered by collateral agreements (percent)	100.00%		100.00%