Fair Value of Assets and Liabilities - Balances of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets:
Available-for-Sale: Fair Value	$ 2,844,823	$ 4,276,056
Loans Held for Sale	1,035	26,746
Derivatives	47,717	42,011
Debt Securities Issued by States and Political Subdivisions
Assets:
Available-for-Sale: Fair Value	95,265	75,818
Debt Securities Issued by Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	48,628	1,780
Debt Securities Issued by Corporations
Assets:
Available-for-Sale: Fair Value	794,658	383,113
Residential - Government Agencies
Assets:
Available-for-Sale: Fair Value	732,828	1,319,042
Residential - U.S. Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	793,871	2,090,326
Commercial - Government Agencies - Sponsored Agencies
Assets:
Available-for-Sale: Fair Value	145,667	155,890
Mortgage-Backed Securities
Assets:
Available-for-Sale: Fair Value	1,672,366	3,565,258
Fair Value, Measurements, Recurring
Assets:
Available-for-Sale: Fair Value	2,844,823	4,276,056
Loans Held for Sale	1,035	26,746
Mortgage Servicing Rights	717	800
Other Assets	47,755	56,411
Derivatives	47,717	42,011
Total Assets Measured at Fair Value on a Recurring Basis	2,942,047	4,402,024
Liabilities:
Derivatives	$ 168,037	$ 18,816
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities	Other Liabilities
Total Liabilities Measured at Fair Value on a Recurring Basis	$ 168,037	$ 18,816
Fair Value, Measurements, Recurring | Debt Securities Issued by the U.S. Treasury and Government Agencies
Assets:
Available-for-Sale: Fair Value	233,906	250,087
Fair Value, Measurements, Recurring | Debt Securities Issued by States and Political Subdivisions
Assets:
Available-for-Sale: Fair Value	95,265	75,818
Fair Value, Measurements, Recurring | Debt Securities Issued by Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	48,628	1,780
Fair Value, Measurements, Recurring | Debt Securities Issued by Corporations
Assets:
Available-for-Sale: Fair Value	794,658	383,113
Fair Value, Measurements, Recurring | Residential - Government Agencies
Assets:
Available-for-Sale: Fair Value	732,828	1,319,042
Fair Value, Measurements, Recurring | Residential - U.S. Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	793,871	2,090,326
Fair Value, Measurements, Recurring | Commercial - Government Agencies - Sponsored Agencies
Assets:
Available-for-Sale: Fair Value	145,667	155,890
Fair Value, Measurements, Recurring | Mortgage-Backed Securities
Assets:
Available-for-Sale: Fair Value	1,672,366	3,565,258
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Assets:
Available-for-Sale: Fair Value	141,944	114,845
Loans Held for Sale	0	0
Mortgage Servicing Rights	0	0
Other Assets	47,755	56,411
Derivatives	0	0
Total Assets Measured at Fair Value on a Recurring Basis	189,699	171,256
Liabilities:
Derivatives	$ 0	$ 0
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities	Other Liabilities
Total Liabilities Measured at Fair Value on a Recurring Basis	$ 0	$ 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Debt Securities Issued by the U.S. Treasury and Government Agencies
Assets:
Available-for-Sale: Fair Value	141,944	114,845
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Debt Securities Issued by States and Political Subdivisions
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Debt Securities Issued by Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Debt Securities Issued by Corporations
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Residential - Government Agencies
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Residential - U.S. Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Commercial - Government Agencies - Sponsored Agencies
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Mortgage-Backed Securities
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Assets:
Available-for-Sale: Fair Value	2,702,879	4,161,211
Loans Held for Sale	1,035	26,746
Mortgage Servicing Rights	0	0
Other Assets	0	0
Derivatives	1,822	194
Total Assets Measured at Fair Value on a Recurring Basis	2,705,736	4,188,151
Liabilities:
Derivatives	$ 70	$ 903
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities	Other Liabilities
Total Liabilities Measured at Fair Value on a Recurring Basis	$ 70	$ 903
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Debt Securities Issued by the U.S. Treasury and Government Agencies
Assets:
Available-for-Sale: Fair Value	91,962	135,242
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Debt Securities Issued by States and Political Subdivisions
Assets:
Available-for-Sale: Fair Value	95,265	75,818
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Debt Securities Issued by Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	48,628	1,780
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Debt Securities Issued by Corporations
Assets:
Available-for-Sale: Fair Value	794,658	383,113
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Residential - Government Agencies
Assets:
Available-for-Sale: Fair Value	732,828	1,319,042
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Residential - U.S. Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	793,871	2,090,326
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Commercial - Government Agencies - Sponsored Agencies
Assets:
Available-for-Sale: Fair Value	145,667	155,890
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Mortgage-Backed Securities
Assets:
Available-for-Sale: Fair Value	1,672,366	3,565,258
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3)
Assets:
Available-for-Sale: Fair Value	0	0
Loans Held for Sale	0	0
Mortgage Servicing Rights	717	800
Other Assets	0	0
Derivatives	45,895	41,817
Total Assets Measured at Fair Value on a Recurring Basis	46,612	42,617
Liabilities:
Derivatives	$ 167,967	$ 17,913
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities	Other Liabilities
Total Liabilities Measured at Fair Value on a Recurring Basis	$ 167,967	$ 17,913
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Debt Securities Issued by the U.S. Treasury and Government Agencies
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Debt Securities Issued by States and Political Subdivisions
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Debt Securities Issued by Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Debt Securities Issued by Corporations
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Residential - Government Agencies
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Residential - U.S. Government-Sponsored Enterprises
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Commercial - Government Agencies - Sponsored Agencies
Assets:
Available-for-Sale: Fair Value	0	0
Fair Value, Measurements, Recurring | Significant Other Unobservable Inputs (Level 3) | Mortgage-Backed Securities
Assets:
Available-for-Sale: Fair Value	$ 0	$ 0