v3.22.4
Loans (Activity in Allowance for Loan Losses by Portfolio Segment) (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Jan. 01, 2020
Dec. 31, 2019
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss $ 227,621 $ 248,666      
Commercial Portfolio Segment [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss 104,237 72,091 $ 73,843   $ 51,593
Financing Receivable, Credit Loss, Expense (Reversal) 34,479 (2,160) 15,156    
Financing Receivable, Allowance for Credit Loss, Writeoff (6,575) (5,513) (18,908)    
Financing Receivable, Allowance for Credit Loss, Recovery 4,242 5,921 4,739    
Allowance for Loan and Lease Losses Write-offs, Net (2,333) 408 (14,169)    
Commercial Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss       $ 21,263  
Commercial And Industrial Energy Financing Receivable [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss 18,062 17,217 39,553   37,382
Financing Receivable, Credit Loss, Expense (Reversal) (313) (19,207) 85,889    
Financing Receivable, Allowance for Credit Loss, Writeoff (371) (5,331) (76,107)    
Financing Receivable, Allowance for Credit Loss, Recovery 1,529 2,202 2,842    
Allowance for Loan and Lease Losses Write-offs, Net 1,158 (3,129) (73,265)    
Commercial And Industrial Energy Financing Receivable [Member] | Accounting Standards Update 2016-13 [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss       (10,453)  
Commercial Real Estate Portfolio Segment [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss 90,301 144,936 134,892   31,037
Financing Receivable, Credit Loss, Expense (Reversal) (54,775) 8,101 124,427    
Financing Receivable, Allowance for Credit Loss, Writeoff (702) (399) (7,499)    
Financing Receivable, Allowance for Credit Loss, Recovery 842 2,342 446    
Allowance for Loan and Lease Losses Write-offs, Net 140 1,943 (7,053)    
Commercial Real Estate Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss       (13,519)  
Total consumer real estate loans [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss 8,004 6,585 7,926   4,113
Financing Receivable, Credit Loss, Expense (Reversal) 1,813 (3,061) 1,906    
Financing Receivable, Allowance for Credit Loss, Writeoff (912) (829) (2,186)    
Financing Receivable, Allowance for Credit Loss, Recovery 518 2,549 1,701    
Allowance for Loan and Lease Losses Write-offs, Net (394) 1,720 (485)    
Total consumer real estate loans [Member] | Accounting Standards Update 2016-13 [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss       2,392  
Consumer Loan [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss 7,017 7,837 6,963   8,042
Financing Receivable, Credit Loss, Expense (Reversal) 13,517 10,230 9,632    
Financing Receivable, Allowance for Credit Loss, Writeoff (24,388) (18,614) (17,830)    
Financing Receivable, Allowance for Credit Loss, Recovery 10,051 9,258 9,367    
Allowance for Loan and Lease Losses Write-offs, Net (14,337) (9,356) (8,463)    
Consumer Loan [Member] | Accounting Standards Update 2016-13 [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss       (2,248)  
Loans Receivable [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss 227,621 248,666 263,177   $ 132,167
Financing Receivable, Credit Loss, Expense (Reversal) (5,279) (6,097) 237,010    
Financing Receivable, Allowance for Credit Loss, Writeoff (32,948) (30,686) (122,530)    
Financing Receivable, Allowance for Credit Loss, Recovery 17,182 22,272 19,095    
Allowance for Loan and Lease Losses Write-offs, Net $ (15,766) $ (8,414) $ (103,435)    
Loans Receivable [Member] | Accounting Standards Update 2016-13 [Member]          
Accounts, Notes, Loans and Financing Receivable [Line Items]          
Financing Receivable, Allowance for Credit Loss       $ (2,565)