XML 90 R73.htm IDEA: XBRL DOCUMENT
v3.20.4

Financial Instruments Owned And Financial Instruments Sold, But Not Yet Purchased (Components Of Trading Securities Owned And Trading Securities Sold, But Not Yet Purchased) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | $ 694,028 | $ 972,932
U.S. Government Agency Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | 56,450 | 66,881
Corporate Fixed Income Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | 194,575 | 250,783
Corporate Equity Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | 67,593 | 64,009
State and Municipal Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | 96,150 | 137,211
U.S. Government Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | 46,900 | 9,266
Securities Sold, But Not yet Purchased [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Financial instruments owned, at fair value |  | 437,978 | 662,852
Other | [1] | 11,303 | 15,226
Securities Sold, But Not yet Purchased [Member] | Corporate Fixed Income Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Fixed income securities |  | 162,626 | 140,100
Securities Sold, But Not yet Purchased [Member] | Corporate Equity Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Equity securities |  | 30,848 | 32,047
Securities Sold, But Not yet Purchased [Member] | U.S. Government Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Trading securities owned |  | 91,974 | 243,570
Securities Sold, But Not yet Purchased [Member] | Agency Mortgage-Backed Securities [Member] | Agency Securities |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Trading securities owned |  | 141,227 | 231,909
Securities Owned [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Other | [2] | 15,926 | 55,926
Financial instruments owned, at fair value |  | 694,028 | 972,932
Securities Owned [Member] | U.S. Government Agency Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Trading securities owned |  | 56,450 | 66,881
Securities Owned [Member] | Corporate Fixed Income Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Fixed income securities |  | 194,575 | 250,783
Securities Owned [Member] | Corporate Equity Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Equity securities |  | 67,593 | 64,009
Securities Owned [Member] | State and Municipal Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
State and municipal securities |  | 96,150 | 137,211
Securities Owned [Member] | U.S. Government Securities [Member] |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Trading securities owned |  | 46,900 | 9,266
Securities Owned [Member] | Agency Mortgage-Backed Securities [Member] | Agency Securities |  |  |
Schedule Of Trading Securities And Other Trading Assets [Line Items] |  |  |
Trading securities owned |  | $ 216,434 | $ 388,856
[1] | Includes sovereign debt, U.S. government agency securities, loans, and state and municipal securities.
[2] | Includes loans, asset-backed securities, sovereign debt, and non-agency mortgage-backed securities.

X
- Definition Financial instruments sold but not yet purchased, others at fair value. + References No definition available. + Details
Name: | sf_FinancialInstrumentsSoldNotYetPurchasedOthersAtFairValue
Namespace Prefix: | sf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value of firm holdings in securities classified as other. Includes pledged and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
Name: | us-gaap_FinancialInstrumentsOwnedOtherAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of obligations arising from corporate debt obligations sold short. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 35 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42429-110968 + Details
Name: | us-gaap_FinancialInstrumentsSoldNotYetPurchasedCorporateDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value of obligations arising from state and municipal debt obligations sold short. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 35 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35711043&loc=d3e42429-110968 + Details
Name: | us-gaap_FinancialInstrumentsSoldNotYetPurchasedStateAndMunicipalGovernmentObligations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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_ScheduleOfTradingSecuritiesAndOtherTradingAssetsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
Name: | us-gaap_TradingSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562 + Details
Name: | us-gaap_TradingSecuritiesDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investments in trading equity securities and other forms of trading securities that provide ownership interests. + References No definition available. + Details
Name: | us-gaap_TradingSecuritiesEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_USGovernmentCorporationsAndAgenciesSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_FixedIncomeSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=sf_CorporateEquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SecurityOwnedAndSoldNotYetPurchasedAtFairValueAxis=us-gaap_USGovernmentDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=us-gaap_SecuritiesSoldNotYetPurchasedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnderlyingAssetClassAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_AgencySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=sf_SecuritiesOwnedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |