Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial assets:
Securities available for sale, at fair value	$ 2,405,316	$ 2,386,052
Derivative instruments	26,694	8,007
Financial liabilities:
Derivative instruments	13,337	13,436
Recurring
Financial assets:
Derivative instruments	29,396	17,698
Mortgage loans held for sale in loans held for sale	280,464	453,533
Total financial assets	2,715,176	2,857,283
Financial liabilities:
Derivative instruments	18,923	13,803
Recurring \| Securities available for sale
Financial assets:
Securities available for sale, at fair value	2,405,316	2,386,052
Recurring \| Level 1
Financial assets:
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 \| Securities available for sale
Financial assets:
Securities available for sale, at fair value	0	0
Recurring \| Level 2
Financial assets:
Derivative instruments	29,396	17,698
Mortgage loans held for sale in loans held for sale	280,464	453,533
Total financial assets	2,715,176	2,857,283
Financial liabilities:
Derivative instruments	18,923	13,803
Recurring \| Level 2 \| Securities available for sale
Financial assets:
Securities available for sale, at fair value	2,405,316	2,386,052
Recurring \| Level 3
Financial assets:
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 3 \| Securities available for sale
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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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