Bank Loans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans held for sale	$ 472,804		$ 472,804		$ 423,999
Accrued interest receivable	$ 97,800		$ 97,800		$ 94,000
Collateralized loan portfolio	96.90%		96.90%		97.00%
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans held for sale	$ 472,800		$ 472,800		$ 424,000
Residential Real Estate [Member] | Asset Pledged as Collateral [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans pledged as collateral	7,600,000		7,600,000		7,400,000
Other Income
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gains (losses) recognized from sale of loans	(1,500)	$ (2,000)	(2,900)	$ (2,600)
Accounting Standards Update 2016-13 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	6,800	6,100	11,400	11,500
Credit Loss Reserves Net	3,000	7,800	8,200	12,700
Accounting Standards Update 2016-13 [Member] | Unfunded Commitment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowances for unfunded credit commitments	3,900		3,500
Reserve for unfunded credit commitment for credit loss		$ 1,700		$ 1,300
Accounting Standards Update 2016-13 [Member] | Employee Retention Awards [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Credit Loss Reserves Net			300
Stifel Bancorp [Member] | Executive Officers and Directors of Certain Affiliated Entities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans outstanding amount	$ 38,000		$ 38,000		$ 46,000