Fair Value Measurements (Details 2) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Fair value measurements
Investment securities available-for-sale	$ 1,836,389	$ 1,863,041
Assets:
Mortgages held for sale	5,525	13,284
U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	1,057,833	1,084,006
U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	114,796	95,701
Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	646,867	659,727
Corporate debt securities
Fair value measurements
Investment securities available-for-sale	16,309	23,009
Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	584	598
Total
Fair value measurements
Investment securities available-for-sale	1,836,389	1,863,041
Assets:
Mortgages held for sale	5,525	13,284
Level 1
Fair value measurements
Investment securities available-for-sale	583,615	561,950
Assets:
Mortgages held for sale	0	0
Level 2
Fair value measurements
Investment securities available-for-sale	1,248,259	1,299,242
Assets:
Mortgages held for sale	5,525	13,284
Level 3
Fair value measurements
Investment securities available-for-sale	4,515	1,849
Assets:
Mortgages held for sale	0	0
Recurring basis \| Total
Fair value measurements
Investment securities available-for-sale	1,836,389	1,863,041
Assets:
Mortgages held for sale	5,525	13,284
Total	1,855,346	1,897,060
Liabilities:
Total	13,686	21,172
Recurring basis \| Total \| Interest rate swap contracts
Assets:
Accrued income and other assets	13,432	20,735
Liabilities:
Accrued expenses and other liabilities	13,686	21,172
Recurring basis \| Total \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	1,057,833	1,084,006
Recurring basis \| Total \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	114,796	95,701
Recurring basis \| Total \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	646,867	659,727
Recurring basis \| Total \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	16,309	23,009
Recurring basis \| Total \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	584	598
Recurring basis \| Level 1
Fair value measurements
Investment securities available-for-sale	583,615	561,950
Assets:
Mortgages held for sale	0	0
Total	583,615	561,950
Liabilities:
Total	0	0
Recurring basis \| Level 1 \| Interest rate swap contracts
Assets:
Accrued income and other assets	0	0
Liabilities:
Accrued expenses and other liabilities	0	0
Recurring basis \| Level 1 \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	583,615	561,950
Recurring basis \| Level 1 \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| Level 1 \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| Level 1 \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| Level 1 \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| Level 2
Fair value measurements
Investment securities available-for-sale	1,248,259	1,299,242
Assets:
Mortgages held for sale	5,525	13,284
Total	1,267,216	1,333,261
Liabilities:
Total	13,686	21,172
Recurring basis \| Level 2 \| Interest rate swap contracts
Assets:
Accrued income and other assets	13,432	20,735
Liabilities:
Accrued expenses and other liabilities	13,686	21,172
Recurring basis \| Level 2 \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	474,218	522,056
Recurring basis \| Level 2 \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	110,281	93,852
Recurring basis \| Level 2 \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	646,867	659,727
Recurring basis \| Level 2 \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	16,309	23,009
Recurring basis \| Level 2 \| Foreign government and other securities
Fair value measurements
Investment securities available-for-sale	584	598
Recurring basis \| Level 3
Fair value measurements
Investment securities available-for-sale	4,515	1,849
Assets:
Mortgages held for sale	0	0
Total	4,515	1,849
Liabilities:
Total	0	0
Recurring basis \| Level 3 \| Interest rate swap contracts
Assets:
Accrued income and other assets	0	0
Liabilities:
Accrued expenses and other liabilities	0	0
Recurring basis \| Level 3 \| U.S. Treasury and Federal agencies securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| Level 3 \| U.S. States and political subdivisions securities
Fair value measurements
Investment securities available-for-sale	4,515	1,849
Recurring basis \| Level 3 \| Mortgage-backed securities - Federal agencies
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| Level 3 \| Corporate debt securities
Fair value measurements
Investment securities available-for-sale	0	0
Recurring basis \| 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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