Consolidated Statements Of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues:
Revenue from contracts with customers		$ 636,899	$ 585,587	$ 1,875,321	$ 1,661,442
Principal transactions		140,883	97,847	445,566	298,343
Interest		114,411	178,784	403,956	557,795
Other income		20,258	8,747	50,979	34,461
Total revenues		897,122	865,716	2,743,414	2,539,262
Interest expense		13,822	44,144	51,263	146,483
Net revenues	[1]	883,300	821,572	2,692,151	2,392,779
Non-interest expenses:
Compensation and benefits		533,638	486,160	1,657,991	1,411,135
Occupancy and equipment rental		68,598	58,649	200,935	178,566
Communications and office supplies		40,123	36,817	124,293	107,583
Commissions and floor brokerage		13,254	10,542	43,273	32,506
Provision for credit losses		(1,353)	929	33,925	5,565
Other operating expenses		70,647	77,721	215,275	220,879
Total non-interest expenses		724,907	670,818	2,275,692	1,956,234
Income from operations before income tax expense		158,393	150,754	416,459	436,545
Provision for income taxes		37,866	40,632	101,456	117,227
Net income		120,527	110,122	315,003	319,318
Net income applicable to non-controlling interests			708		1,612
Net income applicable to Stifel Financial Corp.		120,527	109,414	315,003	317,706
Preferred dividends		9,897	4,844	19,584	12,476
Net income available to common shareholders		$ 110,630	$ 104,570	$ 295,419	$ 305,230
Earnings per common share:
Basic		$ 1.57	$ 1.47	$ 4.17	$ 4.21
Diluted		1.46	1.34	3.90	3.87
Cash dividends declared per common share		$ 0.17	$ 0.15	$ 0.51	$ 0.45
Weighted-average number of common shares outstanding:
Basic		70,627	71,197	70,814	72,512
Diluted		75,850	78,144	75,712	78,826
Commissions [Member]
Revenues:
Revenue from contracts with customers		$ 172,654	$ 163,920	$ 560,780	$ 484,350
Investment Banking [Member]
Revenues:
Revenue from contracts with customers		218,134	198,790	614,637	540,247
Asset Management and Service Fees [Member]
Revenues:
Revenue from contracts with customers		$ 230,782	$ 217,628	$ 667,496	$ 624,066

[1] No individual client accounted for more than 10 percent of total net revenues for the three and nine months ended September 30, 2020 or 2019.