Elective deferrals vested percentage.

No definition available.

Name:	sf_ElectiveDeferralsVestedPercentage
Namespace Prefix:	sf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of earnings deferred into company stock units.

+ References

No definition available.

+ Details

Name:	sf_PercentageOfEarningsDeferredIntoCompanyStockUnits
Namespace Prefix:	sf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of earnings deferred into company stock units additional elective deferral.

+ References

No definition available.

+ Details

Name:	sf_PercentageOfEarningsDeferredIntoCompanyStockUnitsAdditionalElectiveDeferral
Namespace Prefix:	sf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of earnings deferred into company stock units company match.

+ References

No definition available.

+ Details

Name:	sf_PercentageOfEarningsDeferredIntoCompanyStockUnitsCompanyMatch
Namespace Prefix:	sf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of earnings deferred into company stock units deferred in mutual funds.

+ References

No definition available.

+ Details

Name:	sf_PercentageOfEarningsDeferredIntoCompanyStockUnitsDeferredInMutualFunds
Namespace Prefix:	sf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Sharebased compensation arrangement by share based payment award award shares potentially converted range percentage.

+ References

No definition available.

+ Details

Name:	sf_SharebasedCompensationArrangementByShareBasedPaymentAwardAwardSharesPotentiallyConvertedRangePercentage
Namespace Prefix:	sf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in additional paid in capital (APIC) resulting from a tax benefit (deficiency) associated with an share-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

+ Details

Name:	us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

+ Details

Name:	us-gaap_DeferredCompensationLiabilityCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(h))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_Investments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_MutualFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=sf_IncentiveStockAwardPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201609Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=sf_PerformanceBasedRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=sf_StifelNicolausWealthAccumulationPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensationAxis=us-gaap_DeferredCompensationShareBasedPaymentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Employee Incentive, Deferred Compensation, And Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to grant			5,900,000
Stock-based compensation			$ 55,266	$ 94,349
Provision for income tax expense (benefit)	$ 30,387	$ 6,022	43,894	22,880
Investments, at fair value	128,332		128,332		$ 133,563
Deferred compensation liability	5,300		5,300		8,600
Contributions to the Profit Sharing Plan	$ 3,300	1,600	$ 3,700	2,900
Mutual Funds [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of earnings deferred into mutual funds	2.00%		2.00%
Investments, at fair value	$ 12,400		$ 12,400		$ 11,300
Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	34,400	65,900	65,600	94,800
Tax impact related to stock-based compensation provision		$ 1,000		$ 5,200
Incentive Stock Award Plans [Member] \| ASU No. 2016-09 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Provision for income tax expense (benefit)	$ (200)		$ (17,100)
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock units outstanding	19,600,000		19,600,000
Unvested stock units outstanding	16,200,000		16,200,000
Unrecognized compensation expense related to non-vested options	$ 361,200		$ 361,200
Weighted-average period, compensation cost expected to recognized, in years			3 years
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			5 years
Total number of stock units outstanding	600,000		600,000
Unvested stock units outstanding	600,000		600,000
Award performance period			4 years
SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Elective deferrals vested percentage	100.00%		100.00%
Percentage of earnings deferred into company stock units	4.00%		4.00%
Percentage of earnings deferred into company stock units, Company match	25.00%		25.00%
Percentage of earnings deferred into company stock units, Additional elective deferral			1.00%
Minimum [Member] \| Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Minimum [Member] \| Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Minimum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Minimum [Member] \| Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares			0.00%
Minimum [Member] \| SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Maximum [Member] \| Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			8 years
Maximum [Member] \| Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years
Maximum [Member] \| Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares			200.00%
Maximum [Member] \| SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			8 years