Goodwill and Other Intangible Assets - Carrying amount (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill and other intangible assets
Total intangibles subject to amortization, net	$ 20,400	$ 14,014
Goodwill	452,007	367,809	$ 327,425
Total goodwill and other intangible assets, net	472,407	381,823
Core deposit intangible
Goodwill and other intangible assets
Intangibles subject to amortization, gross	38,192	36,162
Less: accumulated amortization	(25,870)	(22,148)
Total intangibles subject to amortization, net	12,322	14,014
Customer relationship intangible
Goodwill and other intangible assets
Intangibles subject to amortization, gross	8,400	0
Less: accumulated amortization	(322)	0
Total intangibles subject to amortization, net	$ 8,078	$ 0