Continuing Involvement with Transferred Financial Assets, Principal Amount Outstanding

No definition available.

Name:	sov_ContinuingInvolvementwithTransferredFinancialAssetsPrincipalAmountOutstanding
Namespace Prefix:	sov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Net Credit Losses on Securitized Loans

+ References

No definition available.

+ Details

Name:	sov_NetCreditLossesonSecuritizedLoans
Namespace Prefix:	sov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This is the principal amount outstanding greater than 90 days past due for securitized loans only (across all types of loans).

+ References

No definition available.

+ Details

Name:	sov_PrincipalAmountOutstandingOnLoansSecuritizedOrAssetBackedFinancingArrangementGreaterThan90DaysPastDue
Namespace Prefix:	sov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Proceeds from Securitization of Retail Installment Contracts

+ References

No definition available.

+ Details

Name:	sov_ProceedsfromSecuritizationofRetailInstallmentContracts
Namespace Prefix:	sov_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount owed to the reporting entity by counterparties in securitized loan transactions.

+ References

No definition available.

+ Details

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

- Definition

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that have been derecognized. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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

- Definition

A gain (loss) realized on a transfer, accounted for as a sale, of all or a portion of financial assets in which the transferor surrenders control and receives consideration other than a beneficial interest in the assets transferred. Reflects the amount of sales proceeds in excess of, or deficient from, the sum of the carrying amounts of transferred financial assets plus transaction costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7,9)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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

- Definition

This is the principal amount outstanding for securitized loans only (across all types of loans).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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

- Details

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

- Details

Name:	us-gaap_QualitativeAndQuantitativeInformationTransferorsContinuingInvolvementTransferredFinancialAssetsByTransferOrTransfereeAxis=sov_ChryslerCapitalSecuritizationsMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_QualitativeAndQuantitativeInformationTransferorsContinuingInvolvementTransferredFinancialAssetsByTransferOrTransfereeAxis=sov_TrustsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=sov_SecuritizationEntitiesMember
Namespace Prefix:
Data Type:	na
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Period Type:

VARIABLE INTEREST ENTITIES (Details) (USD $)	3 Months Ended	8 Months Ended	9 Months Ended
VARIABLE INTEREST ENTITIES (Details) (USD $)	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Variable Interest Entity [Line Items]
Proceeds from securitization of retail installment contracts	$ 1,000,000,000	$ 1,800,000,000
Gain on securitization of financial assets	39,100,000	71,600,000
Securitization Entities [Member]
Variable Interest Entity [Line Items]
Receivable from securitizations	6,200,000	6,200,000	6,200,000		5,500,000
Securitization Entities [Member] \| Home Equity Loans and Lines of Credit [Member]
Variable Interest Entity [Line Items]
Principal amount outstanding on loans securitized	37,900,000	37,900,000	37,900,000		41,500,000
Principal amount outstanding on loans securitized, greater than 90 days past due	15,900,000	15,900,000	15,900,000		15,300,000
Net credit losses on securitized loans			100,000	300,000
Trusts [Member] \| VIE, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Gross retail installment contracts transferred to consolidated Trusts	22,600,000,000	22,600,000,000	22,600,000,000
Chrysler Capital Securitizations [Member] \| VIE, Not Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Gross retail installment contracts sold in off-balance sheet securitizations	$ 2,400,000,000	$ 2,400,000,000	$ 2,400,000,000