Derivative and Hedging Activities, Derivative Instruments Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Not Designated as Hedging Instrument | Trading Assets [Member] | Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	$ 2,726,738	$ 2,707,204
Derivative, Fair Value, Net	54,479	52,796
Not Designated as Hedging Instrument | Trading Assets [Member] | Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	92,285	117,879
Derivative, Fair Value, Net	1,737	721
Not Designated as Hedging Instrument | Trading Assets [Member] | Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	284,655	331,727
Derivative, Fair Value, Net	21,705	35,426
Not Designated as Hedging Instrument | Trading Liabilities [Member] | Interest rate-related instruments — customer and mirror
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	2,726,738	2,707,204
Derivative, Fair Value, Net	(55,008)	(52,653)
Not Designated as Hedging Instrument | Trading Liabilities [Member] | Foreign currency exchange forwards
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	103,238	69,153
Derivative, Fair Value, Net	(1,665)	(675)
Not Designated as Hedging Instrument | Trading Liabilities [Member] | Commodity contracts
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	284,656	315,861
Derivative, Fair Value, Net	(21,186)	(34,340)
Not Designated as Hedging Instrument | Other Assets [Member] | Interest rate lock commitments (mortgage)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	269,075	191,222
Derivative, Fair Value, Net	3,032	2,208
Not Designated as Hedging Instrument | Other Assets [Member] | Purchased options (time deposit)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	7,885	11,185
Derivative, Fair Value, Net	156	109
Not Designated as Hedging Instrument | Other liabilities | Forward commitments (mortgage)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	191,112	139,984
Derivative, Fair Value, Net	(1,825)	(2,072)
Not Designated as Hedging Instrument | Other liabilities | Written options (time deposit)
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	7,885	11,185
Derivative, Fair Value, Net	(156)	(109)
Designated as Hedging Instrument | Other liabilities | interest rate product [Member]
Derivative Instruments Not Designated as Hedging Instruments [Abstract]
Notional Amount	500,000	500,000
Derivative, Fair Value, Net	$ (128)	$ (40)