Fair Value of Financial Assets and Liabilities, Fair Value Measurements of Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	$ 1,503,165	$ 1,455,429
Equity securities at fair value	2,352	2,253
U.S. Treasury and Government Agencies [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	451,731	295,770
State and Political Subdivisions [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	302,662	334,203
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	655,213	730,809
Asset-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	93,559	94,647
Recurring [Member]
Assets measured - recurring basis [Abstract]
Equity securities at fair value	2,352	2,253
Mortgage servicing rights	7,748	6,774
Recurring [Member] | U.S. Treasury and Government Agencies [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	451,731	295,770
Recurring [Member] | State and Political Subdivisions [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	302,662	334,203
Recurring [Member] | U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	655,213	730,809
Recurring [Member] | Asset-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	93,559	94,647
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Recurring [Member]
Assets measured - recurring basis [Abstract]
Equity securities at fair value	0	0
Mortgage servicing rights	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Recurring [Member] | U.S. Treasury and Government Agencies [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	402,275	242,214
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Recurring [Member] | State and Political Subdivisions [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Recurring [Member] | U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Recurring [Member] | Asset-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	0	0
Significant Other Observable Inputs (Level 2) [Member] | Recurring [Member]
Assets measured - recurring basis [Abstract]
Equity securities at fair value	0	0
Mortgage servicing rights	0	0
Significant Other Observable Inputs (Level 2) [Member] | Recurring [Member] | U.S. Treasury and Government Agencies [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	49,456	53,556
Significant Other Observable Inputs (Level 2) [Member] | Recurring [Member] | State and Political Subdivisions [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	302,662	334,203
Significant Other Observable Inputs (Level 2) [Member] | Recurring [Member] | U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	655,213	730,809
Significant Other Observable Inputs (Level 2) [Member] | Recurring [Member] | Asset-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	93,559	94,647
Significant Unobservable Inputs (Level 3) [Member] | Recurring [Member]
Assets measured - recurring basis [Abstract]
Equity securities at fair value	2,352	2,253
Mortgage servicing rights	7,748	6,774
Significant Unobservable Inputs (Level 3) [Member] | Recurring [Member] | U.S. Treasury and Government Agencies [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) [Member] | Recurring [Member] | State and Political Subdivisions [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) [Member] | Recurring [Member] | U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	0	0
Significant Unobservable Inputs (Level 3) [Member] | Recurring [Member] | Asset-backed Securities [Member]
Assets measured - recurring basis [Abstract]
Debt securities available-for-sale	$ 0	$ 0