Commitments and Contingencies (Reserve for Unfunded Commitments) (Detail) - SEC Schedule, 12-09, Allowance, Credit Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, beginning of period	$ 20,149	$ 11,974	$ 13,104	$ 12,755
ACL assumed from Sterling	0	0	6,749	0
Provision (benefit) for credit losses	5,180	196	5,476	(585)
Balance, end of period	$ 25,329	$ 12,170	$ 25,329	$ 12,170