Loan Portfolio and Allowance for Credit Losses , Type of Collateral Dependent Loans by Portfolio Segment (Details) $ in Thousands	Mar. 31, 2022 USD ($)
Loans and Leases Receivable [Abstract]
Total loans	$ 4,464,354
Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	17,922
Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Commercial [Member]
Loans and Leases Receivable [Abstract]
Total loans	192,408
Commercial [Member] | Commercial Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	171,230
Commercial [Member] | Commercial Real Estate [Member] | Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	301
Commercial [Member] | Commercial Real Estate [Member] | Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Commercial [Member] | Commercial Real Estate [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Commercial [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	21,178
Commercial [Member] | Other [Member] | Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	4
Commercial [Member] | Other [Member] | Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Commercial [Member] | Other [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Real Estate Mortgage - 1 to 4 Family [Member]
Loans and Leases Receivable [Abstract]
Total loans	4,262,551
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member]
Loans and Leases Receivable [Abstract]
Total loans	3,965,962
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	15,417
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Real Estate Mortgage - 1 to 4 Family [Member] | First Mortgages [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member]
Loans and Leases Receivable [Abstract]
Total loans	60,472
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member] | Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	159
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member] | Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Loans [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member]
Loans and Leases Receivable [Abstract]
Total loans	236,117
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member] | Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	2,041
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member] | Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Real Estate Mortgage - 1 to 4 Family [Member] | Home Equity Lines of Credit [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Installment [Member]
Loans and Leases Receivable [Abstract]
Total loans	9,395
Installment [Member] | Real Estate [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Installment [Member] | Investment Securities/Cash [Member]
Loans and Leases Receivable [Abstract]
Total loans	0
Installment [Member] | Other [Member]
Loans and Leases Receivable [Abstract]
Total loans	$ 0