Goodwill and Other Intangible Assets - Carrying Amount (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Goodwill and other intangible assets
Total intangible assets subject to amortization	$ 66,286	$ 70,173
Goodwill	921,253	919,914	$ 896,718	$ 751,174
Total goodwill and other intangible assets, net	987,539	990,087
Core deposit intangible
Goodwill and other intangible assets
Intangibles subject to amortization, gross	100,694	104,174
Less: accumulated amortization	(40,704)	(40,495)
Total intangible assets subject to amortization	59,990	63,679
Customer relationship intangible
Goodwill and other intangible assets
Intangibles subject to amortization, gross	8,400	8,400
Less: accumulated amortization	(2,104)	(1,906)
Total intangible assets subject to amortization	$ 6,296	$ 6,494