Fair Value Of Financial Instruments (Estimated Fair Values Of Financial Instruments Not Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell	[1]	$ 478,091	$ 248,588
Held-to-maturity securities	[2]	3,321,880	3,040,554
Securities sold under agreements to repurchase	[3]	243,999	268,546
Bank deposits		12,050,474	11,527,483
Borrowings		105,000	377,000
Senior notes		796,296	795,891
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		661,689	877,295
Cash segregated for regulatory purposes		150	73,235
Securities purchased under agreements to resell		478,091	248,588
Held-to-maturity securities		3,321,880	3,040,554
Loans held for sale		139,676	228,588
Bank loans		5,994,527	5,633,804
Securities sold under agreements to repurchase		243,999	268,546
Bank deposits		11,366,970	11,092,185
Federal Home Loan Bank advances		790,000	500,000
Borrowings		105,000	377,000
Senior notes		811,318	799,632
Debentures to Stifel Financial Capital Trusts		50,413	52,525
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		661,689	877,295
Cash segregated for regulatory purposes		150	73,235
Securities purchased under agreements to resell		478,091	227,983
Securities sold under agreements to repurchase			149,881
Federal Home Loan Bank advances		790,000	500,000
Borrowings		105,000	377,000
Senior notes		811,318	799,632
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell			20,605
Held-to-maturity securities		3,119,542	2,830,869
Loans held for sale		139,676	228,588
Bank loans		5,994,527	5,633,804
Securities sold under agreements to repurchase		243,999	118,665
Bank deposits		11,366,970	11,092,185
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity securities		202,338	209,685
Debentures to Stifel Financial Capital Trusts		$ 50,413	$ 52,525

[1] Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $474.1 million and $248.5 million at June 30, 2017 and December 31, 2016, respectively.

[2] Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.

[3] Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $263.8 million and $299.3 million at June 30, 2017 and December 31, 2016, respectively.