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Loans Receivable, Net - Summary of Loans Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Summary of Loans Receivable
Loans receivable	$ 16,851,991		$ 16,198,082
Allowance for credit losses	(200,955)	$ (198,779)	(192,757)	$ (189,385)	$ (186,604)	$ (182,283)
Loans receivable, net	16,651,036		16,005,325
Net deferred origination (fees) costs included in loans receivable	(25,875)		(25,577)
Net purchase accounting (discounts) premiums included in loans receivable	(23,865)		(13,802)
Accrued interest receivable on loans	75,845		67,362
Residential real estate
Summary of Loans Receivable
Loans receivable	1,771,528		1,704,544
Allowance for credit losses	(24,653)	(24,166)	(22,325)	(20,847)	(19,974)	(19,683)
Commercial real estate
Summary of Loans Receivable
Loans receivable	10,713,964		10,303,306
Allowance for credit losses	(136,346)	(135,153)	(130,924)	(129,598)	(130,253)	(125,816)
Other commercial
Summary of Loans Receivable
Loans receivable	3,066,028		2,901,863
Allowance for credit losses	(22,219)	(22,094)	(21,194)	(21,797)	(21,164)	(21,454)
Home equity
Summary of Loans Receivable
Loans receivable	905,884		888,013
Allowance for credit losses	(11,261)	(10,999)	(11,766)	(11,053)	(10,570)	(10,759)
Other consumer
Summary of Loans Receivable
Loans receivable	394,587		400,356
Allowance for credit losses	$ (6,476)	$ (6,367)	$ (6,548)	$ (6,090)	$ (4,643)	$ (4,571)