(Reserve for Unfunded Commitments) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accounting Standards Update 2016-13 [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 0	$ 0	$ 0	$ 9,139
SEC Schedule, 12-09, Allowance, Credit Loss [Member]
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	12,800	10,084	12,755	2,367
(Benefit) provision	(826)	655	(781)	(767)
Ending balance	$ 11,974	$ 10,739	$ 11,974	$ 10,739