Regulatory Capital Requirements (Schedule Of Total Risk-Based, Tier 1 Risk-Based, And Tier 1 Leverage Ratios) (Details) $ in Thousands	Sep. 30, 2016 USD ($)
Stifel Financial Corp. [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Common equity tier 1, Actual Amount	$ 1,748,315
Common equity tier 1, Actual Ratio	22.00%
Common equity tier 1, For Capital Adequacy Purposes Amount	$ 476,421
Common equity tier 1, For Capital Adequacy Purposes Ratio	6.00%
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 635,228
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	8.00%
Total capital, Actual Amount	$ 1,788,163
Total capital, Actual Ratio	22.50%
Total capital, For Capital Adequacy Purposes Amount	$ 635,228
Total capital, For Capital Adequacy Purposes Ratio	8.00%
Total capital, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 794,035
Total capital, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%
Tier 1 leverage, Actual Amount	$ 1,748,315
Tier 1 leverage, Actual Ratio	11.80%
Tier 1 leverage, For Capital Adequacy Purposes Amount	$ 594,689
Tier 1 leverage, For Capital Adequacy Purposes Ratio	4.00%
Tier 1 leverage, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 743,361
Tier 1 leverage, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%
Stifel Financial Corp. [Member] | Common Stock [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Common equity tier 1, Actual Amount	$ 1,544,935
Common equity tier 1, Actual Ratio	19.50%
Common equity tier 1, For Capital Adequacy Purposes Amount	$ 357,316
Common equity tier 1, For Capital Adequacy Purposes Ratio	4.50%
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 516,123
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.50%
Stifel Bank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Common equity tier 1, Actual Amount	$ 741,927
Common equity tier 1, Actual Ratio	13.70%
Common equity tier 1, For Capital Adequacy Purposes Amount	$ 324,081
Common equity tier 1, For Capital Adequacy Purposes Ratio	6.00%
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 432,108
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	8.00%
Total capital, Actual Amount	$ 781,829
Total capital, Actual Ratio	14.50%
Total capital, For Capital Adequacy Purposes Amount	$ 432,108
Total capital, For Capital Adequacy Purposes Ratio	8.00%
Total capital, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 540,135
Total capital, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%
Tier 1 leverage, Actual Amount	$ 741,927
Tier 1 leverage, Actual Ratio	7.50%
Tier 1 leverage, For Capital Adequacy Purposes Amount	$ 396,416
Tier 1 leverage, For Capital Adequacy Purposes Ratio	4.00%
Tier 1 leverage, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 495,520
Tier 1 leverage, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%
Stifel Bank [Member] | Common Stock [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Common equity tier 1, Actual Amount	$ 741,927
Common equity tier 1, Actual Ratio	13.70%
Common equity tier 1, For Capital Adequacy Purposes Amount	$ 243,061
Common equity tier 1, For Capital Adequacy Purposes Ratio	4.50%
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 351,087
Common equity tier 1, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.50%