Derivative Financial Instruments - Summary of Fair Value of Derivative Financial Instruments (Detail) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Total derivative assets	$ 149,873,000	$ 51,301,000
Total derivative liabilities	35,219,000	12,393,000
Fair values of counterparty interest rate swaps	0
Interest rate contracts net adjustment	88,900,000	31,600,000
Derivatives designated as hedging instruments
Derivative [Line Items]
Total derivative assets	21,630,000	7,157,000
Total derivative liabilities	1,443,000	1,046,000
Derivatives designated as hedging instruments | Interest rate contracts
Derivative [Line Items]
Total derivative assets	21,630,000	7,157,000
Total derivative liabilities	1,443,000	1,046,000
Derivatives not designated as hedging instruments
Derivative [Line Items]
Total derivative assets	128,243,000	44,144,000
Total derivative liabilities	33,776,000	11,347,000
Derivatives not designated as hedging instruments | Interest rate contracts
Derivative [Line Items]
Total derivative assets	114,839,000	42,224,000
Total derivative liabilities	26,630,000	10,883,000
Derivatives not designated as hedging instruments | Mortgage contracts
Derivative [Line Items]
Total derivative assets	13,081,000	1,702,000
Total derivative liabilities	6,913,000	354,000
Derivatives not designated as hedging instruments | Foreign currency contracts
Derivative [Line Items]
Total derivative assets	323,000	218,000
Total derivative liabilities	$ 233,000	$ 110,000