Fair Value Measurements - Fair Value of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financial assets:
Securities available for sale, at fair value	$ 2,386,052	$ 1,343,457
Derivative instruments	8,007	3,866
Financial liabilities:
Derivative instruments	13,436	21,107
Trust preferred securities
Financial assets:
Securities available for sale, at fair value		9,012
Other debt securities
Financial assets:
Securities available for sale, at fair value	37,464	65,607
Recurring
Financial assets:
Securities available for sale, at fair value	2,386,052	1,343,457
Derivative instruments	17,698	33,574
Mortgage loans held for sale in loans held for sale	453,533	417,771
Total financial assets	2,857,283	1,794,802
Financial liabilities:
Derivative instruments	13,803	21,107
Recurring \| Trust preferred securities
Financial assets:
Securities available for sale, at fair value		9,012
Recurring \| Other debt securities
Financial assets:
Securities available for sale, at fair value	2,386,052	1,334,445
Recurring \| Level 1
Financial assets:
Securities available for sale, at fair value	0	0
Derivative instruments	0	0
Mortgage loans held for sale in loans held for sale	0	0
Total financial assets	0	0
Financial liabilities:
Derivative instruments	0	0
Recurring \| Level 1 \| Trust preferred securities
Financial assets:
Securities available for sale, at fair value		0
Recurring \| Level 1 \| Other debt securities
Financial assets:
Securities available for sale, at fair value	0	0
Recurring \| Level 2
Financial assets:
Securities available for sale, at fair value	2,386,052	1,334,445
Derivative instruments	17,698	33,574
Mortgage loans held for sale in loans held for sale	453,533	417,771
Total financial assets	2,857,283	1,785,790
Financial liabilities:
Derivative instruments	13,803	21,107
Recurring \| Level 2 \| Trust preferred securities
Financial assets:
Securities available for sale, at fair value		0
Recurring \| Level 2 \| Other debt securities
Financial assets:
Securities available for sale, at fair value	2,386,052	1,334,445
Recurring \| Level 3
Financial assets:
Securities available for sale, at fair value	0	9,012
Derivative instruments	0	0
Mortgage loans held for sale in loans held for sale	0	0
Total financial assets	0	9,012
Financial liabilities:
Derivative instruments	0	0
Recurring \| Level 3 \| Trust preferred securities
Financial assets:
Securities available for sale, at fair value		9,012
Recurring \| Level 3 \| Other debt securities
Financial assets:
Securities available for sale, at fair value	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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