Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income		$ 503,472	$ 449,986	$ 393,968
Other comprehensive income/(loss), net of tax:
Changes in unrealized gains/(losses) on available-for-sale securities, net of tax	[1],[2],[3],[4]	33,133	60,288	(36,254)
Changes in unrealized losses on cash flow hedging instruments, net of tax	[2],[4],[5]	(651)	(4,402)	(792)
Foreign currency translation adjustment, net of tax	[2],[4]	6,862	4,932	(5,691)
Total other comprehensive income/(loss), net of tax		39,344	60,818	(42,737)
Comprehensive income		542,816	510,804	351,231
Net income applicable to non-controlling interest			1,590
Comprehensive income applicable to Stifel Financial Corp.		$ 542,816	$ 509,214	$ 351,231

[1] As part of the adoption of ASU 2019-04, in the third quarter of 2019, the Company made a one-time election to transfer a portion of its held-to-maturity securities to available-for-sale. The transfer resulted in a net of tax increase to comprehensive income of $17.9 million. See Notes 2 and 7 for additional information on the transfer.

[2] Net of a tax expense of $11.5 million, tax expense of $20.2 million, and tax benefit of $11.2 million for the years ended December 31, 2020, 2019, and 2018, respectively.

[3] Reclassifications to earnings were immaterial for the years ended December 31, 2020 and 2019. Amounts are net of reclassifications to earnings of realized losses of $2.9 million for the year ended December 31, 2018.

[4] The adoption of ASU 2018-02 on January 1, 2018, resulted in a reclassification of $3.1 million to retained earnings related to cash flow hedges and investment portfolio risk. The reclassification is reflected in the activity for the year ended December 31, 2018. See Note 2 for further details.

[5] Reclassifications to earnings were immaterial for the year ended December 31, 2020. Amounts are net of reclassifications to earnings of gains of $3.3 million and $4.9 million for the years ended December 31, 2019 and 2018, respectively.