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Loans Receivable, Net - Schedule of Loans Receivable, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	$ 10,123,571		$ 9,918,054
Deferred origination costs, net of fees	8,462		7,488
Allowance for loan credit losses	(63,877)	$ (61,791)	(56,824)	$ (53,521)	$ (52,061)	$ (48,850)
Total loans receivable, net	10,068,156		9,868,718
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	6,943,614		6,791,691
Commercial \| Commercial real estate – investor
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	5,334,279		5,171,952
Commercial \| Commercial real estate – owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	957,216		997,367
Commercial \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	652,119		622,372
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	3,179,957		3,126,363
Allowance for loan credit losses	(852)	$ (871)	(1,106)	$ (1,088)	$ (996)	$ (1,268)
Consumer \| Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	2,928,259		2,861,991
Consumer \| Home equity loans and lines and other consumer (“other consumer”)
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans receivable	$ 251,698		$ 264,372