Debt - Additional Information (Short Term Debt) (Detail) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Short-term Debt [Line Items]
Overnight federal funds borrowed	$ 0	$ 0
Securities sold under agreements to repurchase	106,500,000	69,600,000
Securities Sold under Agreements to Repurchase | Mortgage Backed Securities, Other
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	46,200,000
Securities Sold under Agreements to Repurchase | Mortgage-backed securities
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	46,700,000
Securities Sold under Agreements to Repurchase | Agency Securities
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	23,200,000
Securities Sold under Agreements to Repurchase | US Treasury Notes Securities
Short-term Debt [Line Items]
Securities sold under agreements to repurchase	5,000,000
Federal Home Loan Bank of New York
Short-term Debt [Line Items]
Overnight borrowings	0	100,000,000
Line of Credit
Short-term Debt [Line Items]
Overnight federal funds lines available for borrow	215,000,000
Federal Reserve Bank of New York
Short-term Debt [Line Items]
Borrowings with the Federal Reserve Bank	$ 0	$ 0