Fair Value Measurements (Details 2) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair value measurements
Investment securities available-for-sale	$ 1,863,041	$ 1,197,467
Assets:
Mortgages held for sale	13,284	12,885
U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	1,084,006	619,482
U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	95,701	81,127
Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	659,727	453,789
Corporate debt securities
Fair value measurements
Investment securities available-for-sale	23,009	42,369
Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	598	700
Total
Fair value measurements
Investment securities available-for-sale	1,863,041	1,197,467
Assets:
Mortgages held for sale	13,284	12,885
Level 1
Fair value measurements
Investment securities available-for-sale	561,950	80,285
Assets:
Mortgages held for sale	0	0
Level 2
Fair value measurements
Investment securities available-for-sale	1,299,242	1,115,030
Assets:
Mortgages held for sale	13,284	12,885
Level 3
Fair value measurements
Investment securities available-for-sale	1,849	2,152
Assets:
Mortgages held for sale	0	0
Recurring \| Total
Fair value measurements
Investment securities available-for-sale	1,863,041	1,197,467
Assets:
Mortgages held for sale	13,284	12,885
Total	1,897,060	1,257,006
Liabilities:
Total	21,172	47,681
Recurring \| Total \| Interest rate swap contracts
Assets:
Accrued income and other assets	20,735	46,654
Liabilities:
Accrued expenses and other liabilities	21,172	47,681
Recurring \| Total \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	1,084,006	619,482
Recurring \| Total \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	95,701	81,127
Recurring \| Total \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	659,727	453,789
Recurring \| Total \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	23,009	42,369
Recurring \| Total \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	598	700
Recurring \| Level 1
Fair value measurements
Investment securities available-for-sale	561,950	80,285
Assets:
Mortgages held for sale	0	0
Total	561,950	80,285
Liabilities:
Total	0	0
Recurring \| Level 1 \| Interest rate swap contracts
Assets:
Accrued income and other assets	0	0
Liabilities:
Accrued expenses and other liabilities	0	0
Recurring \| Level 1 \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	561,950	80,285
Recurring \| Level 1 \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 1 \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 1 \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 1 \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 2
Fair value measurements
Investment securities available-for-sale	1,299,242	1,115,030
Assets:
Mortgages held for sale	13,284	12,885
Total	1,333,261	1,174,569
Liabilities:
Total	21,172	47,681
Recurring \| Level 2 \| Interest rate swap contracts
Assets:
Accrued income and other assets	20,735	46,654
Liabilities:
Accrued expenses and other liabilities	21,172	47,681
Recurring \| Level 2 \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	522,056	539,197
Recurring \| Level 2 \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	93,852	78,975
Recurring \| Level 2 \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	659,727	453,789
Recurring \| Level 2 \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	23,009	42,369
Recurring \| Level 2 \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	598	700
Recurring \| Level 3
Fair value measurements
Investment securities available-for-sale	1,849	2,152
Assets:
Mortgages held for sale	0	0
Total	1,849	2,152
Liabilities:
Total	0	0
Recurring \| Level 3 \| Interest rate swap contracts
Assets:
Accrued income and other assets	0	0
Liabilities:
Accrued expenses and other liabilities	0	0
Recurring \| Level 3 \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 3 \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	1,849	2,152
Recurring \| Level 3 \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 3 \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring \| Level 3 \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	$ 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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