Regulatory Capital Requirements (Schedule Of Total Risk-Based, Tier 1 Risk-Based, And Tier 1 Leverage Ratios) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Stifel Financial Corp. [Member]
Total capital to risk-weighted assets, Actual Amount	$ 1,046,286
Total capital to risk-weighted assets, For Capital Adequacy Purposes Amount	322,504
Total capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	403,129
Tier 1 capital to risk-weighted assets, Actual Amount	1,039,892
Tier 1 capital to risk-weighted assets, For Capital Adequacy Purposes Amount	161,252
Tier 1 capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	241,878
Tier 1 capital to adjusted average total assets, Actual Amount	1,039,892
Tier 1 capital to adjusted average total assets, For Capital Adequacy Purposes Amount	207,957
Tier 1 capital to adjusted average total assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	259,947
Total capital to risk-weighted assets, Actual Ratio	26.00%
Total capital to risk-weighted assets, For Capital Adequacy Purposes Ratio	8.00%
Total capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%
Tier 1 capital to risk-weighted assets, Actual Ratio	25.80%
Tier 1 capital to risk-weighted assets, For Capital Adequacy Purposes Ratio	4.00%
Tier 1 capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.00%
Tier 1 capital to adjusted average total assets, Actual Ratio	20.00%
Tier 1 capital to adjusted average total assets, For Capital Adequacy Purposes Ratio	4.00%
Tier 1 capital to adjusted average total assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%
Stifel Bank [Member]
Total capital to risk-weighted assets, Actual Amount	234,543
Total capital to risk-weighted assets, For Capital Adequacy Purposes Amount	158,496
Total capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	198,120
Tier 1 capital to risk-weighted assets, Actual Amount	228,149
Tier 1 capital to risk-weighted assets, For Capital Adequacy Purposes Amount	79,248
Tier 1 capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	118,872
Tier 1 capital to adjusted average total assets, Actual Amount	228,149
Tier 1 capital to adjusted average total assets, For Capital Adequacy Purposes Amount	125,607
Tier 1 capital to adjusted average total assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 157,009
Total capital to risk-weighted assets, Actual Ratio	11.80%
Total capital to risk-weighted assets, For Capital Adequacy Purposes Ratio	8.00%
Total capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%
Tier 1 capital to risk-weighted assets, Actual Ratio	11.50%
Tier 1 capital to risk-weighted assets, For Capital Adequacy Purposes Ratio	4.00%
Tier 1 capital to risk-weighted assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.00%
Tier 1 capital to adjusted average total assets, Actual Ratio	7.30%
Tier 1 capital to adjusted average total assets, For Capital Adequacy Purposes Ratio	4.00%
Tier 1 capital to adjusted average total assets, To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%