Bank Loans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans held for sale	$ 163,511		$ 163,511		$ 205,557
Gains (losses) recognized from sale of loans	2,300	$ 2,700	3,200	$ 5,200
Impaired loans more than 90 days past due	23,500		23,500		24,400
Troubled debt restructurings	7,900		7,900		9,100
Specific allowance	$ 8,348		$ 8,348		$ 8,703
Collateralized loan portfolio	98.10%		98.10%		98.40%
Stifel Bancorp [Member] \| Executive Officers and Directors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans outstanding amount	$ 22,600		$ 22,600		$ 28,800
Stifel Bancorp [Member] \| Executive Officers and Directors of Certain Affiliated Entities [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans outstanding amount	$ 22,600		$ 22,600		$ 28,800

Collateralized loan portfolio.

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- Definition

Financing receivable troubled debt restructuring amount.

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due after one year (or one business cycle).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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-Section 50
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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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- Definition

Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
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Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

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-Publisher FASB
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- Definition

Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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