Securities - Additional Information (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) Security	Dec. 31, 2023 USD ($) Security
Schedule Of Available For Sale Securities [Line Items]
Available For Sale Securities | Security	40	40
Held to maturity | Security	33	33
Sale of Held - to maturity Securities	$ 0	$ 0
Sale of available-for-sale securities	$ 0	$ 0
Number of held to maturity securities matured or called | Security	0	1
Held-to-maturity securities matured		$ 10,000,000
Purchases of available-for-sale securities	$ 0	0
Purchases of Held-to-maturity securities	$ 0	$ 0
Number of available-for-sale securities with unrealized loss positions | Security	40	40
Number of held-to-maturity securities with unrealized loss positions | Security	30	31
Held to maturity securities, amortized costs	$ 452,955,000	$ 461,748,000
Available-for-sale securities, at fair value	116,044,000	119,902,000
FRBNY
Schedule Of Available For Sale Securities [Line Items]
Held to maturity securities, amortized costs	$ 136,600,000	$ 193,300,000
Number of held-to-maturity securities | Security	11	17
Number of available-for-sale securities | Security	20	26
Available for sale securities fair value	$ 66,000,000	$ 93,300,000