Goodwill and Other Intangible Assets - Goodwill and Other Intangibles (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Total	$ 116,660	$ 128,951
Core Deposit Premium
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	187,467	189,996
Accumulated amortization	(82,517)	(73,980)
Total	104,950	116,016	$ 93,862
Books of Business Intangible
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	22,068	22,068
Accumulated amortization	(10,358)	(9,133)
Total	$ 11,710	$ 12,935	$ 12,373