Derivative Financial Instruments (Offsetting Derivatives) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Derivative instrument asset, Amount Offset, Total	$ (6,364)	$ (7,748)
Derivative instrument asset, Amount Offset	19,272	33,972
Derivative asset	133,481	297,338
Derivative Liability, Fair Value, Amount Offset Against Collateral	6,364	7,748
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	(2,119)	(4,550)
Derivative liability	13,301	392
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(51)	(666)
Derivative Asset, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	(51)	(720)
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(428)	(265)
Derivative Liability, Fair Value, Offset Against Collateral, Net of Not Subject to Master Netting Arrangement, Policy Election	(428)	(319)
Hedge Accounting Positions [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	25,636	41,774
Derivative instrument asset, Amount Offset, Total	(25,636)	(41,720)
Derivative asset	0	54
Derivative Liability, Fair Value, Gross Liability	8,483	12,352
Derivative Liability, Fair Value, Amount Offset Against Collateral	8,483	12,298
Derivative liability	0	54
Interest Rate Derivatives [Member] | Hedge Accounting Positions [Member]
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset	17,583	40,854
Derivative Liability, Fair Value, Gross Liability	$ 0	$ 110