Name:	cfg_SensitivityAnalysisOfFairValueFairValueMethodTransferorsInterestsInTransferredFinancialAssetsImpactOf1PercentAdverseChangeInOptionAdjustedSpread
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Sensitivity Analysis Of Fair Value, Fair Value Method, Transferor's Interests In Transferred Financial Assets, Impact Of 1 Percent Averse Change In Prepayment Speed

No definition available.

Name:	cfg_SensitivityAnalysisOfFairValueFairValueMethodTransferorsInterestsInTransferredFinancialAssetsImpactOf1PercentAverseChangeInPrepaymentSpeed
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Sensitivity Analysis Of Fair Value, Fair Value Method, Transferor's Interests In Transferred Financial Assets, Impact of 0.5 Percent Adverse Change In Prepayment Speed

No definition available.

Name:	cfg_SensitivityAnalysisOfFairValueFairValueMethodTransferorsInterestsInTransferredFinancialAssetsImpactof0.5PercentAdverseChangeInPrepaymentSpeed
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Sensitivity Analysis Of Fair Value, Fair Value Method, Transferor's Interests In Transferred Financial Assets, Impact of 0.5 Percent Adverse Change Option Adjusted Spread

No definition available.

Name:	cfg_SensitivityAnalysisOfFairValueFairValueMethodTransferorsInterestsInTransferredFinancialAssetsImpactof0.5PercentAdverseChangeOptionAdjustedSpread
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The hypothetical financial impact of a 0.5 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date under the amortization method.

No definition available.

Name:	cfg_SensitivityAnalysisofFairValueAmortizationMethodTransferorsInterestsinTransferredFinancialAssetsImpactof0.5PercentAdverseChangeinDiscountRate
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The hypothetical financial impact of a 0.5 percent (50 basis points) adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date under the amortization method.

No definition available.

Name:	cfg_SensitivityAnalysisofFairValueAmortizationMethodTransferorsInterestsinTransferredFinancialAssetsImpactof0.5PercentAdverseChangeinPrepaymentSpeed
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The hypothetical financial impact of a 1 percent adverse change of the discount rate on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date under the amortization method.

No definition available.

Name:	cfg_SensitivityAnalysisofFairValueAmortizationMethodTransferorsInterestsinTransferredFinancialAssetsImpactof1PercentAdverseChangeinDiscountRate
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The hypothetical financial impact of a 1 percent (100 basis points) adverse change of prepayment speed on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date under the amortization method.

No definition available.

Name:	cfg_SensitivityAnalysisofFairValueAmortizationMethodTransferorsInterestsinTransferredFinancialAssetsImpactof1PercentAdverseChangeinPrepaymentSpeed
Namespace Prefix:	cfg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Sensitivity Analysis of Fair Value Inputs, Basis Spread

No definition available.

Name:	cfg_SensitivityAnalysisofFairValueInputsBasisSpread
Namespace Prefix:	cfg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Servicing Assets And Servicing Liabilities At Amortized Cost, Assumptions Used To Estimate Fair Value [Abstract]

No definition available.

Name:	cfg_ServicingAssetsAndServicingLiabilitiesAtAmortizedCostAssumptionsUsedToEstimateFairValueAbstract
Namespace Prefix:	cfg_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Servicing Assets And Servicing Liabilities At Amortized Cost, Assumptions Used To Estimate Fair Value, Discount Rate

No definition available.

Name:	cfg_ServicingAssetsAndServicingLiabilitiesAtAmortizedCostAssumptionsUsedToEstimateFairValueDiscountRate
Namespace Prefix:	cfg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Servicing Assets And Servicing Liabilities At Amortized Cost, Assumptions Used To Estimate Fair Value, Prepayment Speed

No definition available.

Name:	cfg_ServicingAssetsAndServicingLiabilitiesAtAmortizedCostAssumptionsUsedToEstimateFairValuePrepaymentSpeed
Namespace Prefix:	cfg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Servicing Assets And Servicing Liabilities At Amortized Cost, Assumptions Used To Estimate Fair Value, Weighted Average Life

No definition available.

Name:	cfg_ServicingAssetsAndServicingLiabilitiesAtAmortizedCostAssumptionsUsedToEstimateFairValueWeightedAverageLife
Namespace Prefix:	cfg_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7516967&loc=d3e66267-113978

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

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

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

- References

No definition available.

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

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746

Name:	us-gaap_ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

Name:	us-gaap_ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Name:	us-gaap_ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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.

No definition available.