Consolidated Investment Entities - Fair Value Measurement (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
Revolving lines of credit, capacity	$ 6,872.0
Outstanding borrowings	3,197.0
VIEs \| Senior secured corporate loans
Variable Interest Entity [Line Items]
Unpaid principal exceeds fair value, amount	$ 17.0	$ 43.0
Default of collateral assets, percentage	1.00%	1.00%
Weighted average maturity on debt	8 years 4 months 24 days
VIEs \| Senior secured corporate loans \| Maximum
Variable Interest Entity [Line Items]
Basis spread	10.50%
VIEs \| Senior secured corporate loans \| LIBOR
Variable Interest Entity [Line Items]
Description of variable rate basis	LIBOR
VIEs \| Senior secured corporate loans \| LIBOR \| Minimum
Variable Interest Entity [Line Items]
Basis spread	0.20%
VIEs \| Senior secured corporate loans \| LIBOR \| Maximum
Variable Interest Entity [Line Items]
Basis spread	6.60%
VIEs \| Senior secured corporate loans \| EURIBOR
Variable Interest Entity [Line Items]
Description of variable rate basis	EURIBOR
VIEs \| Senior secured corporate loans \| Prime
Variable Interest Entity [Line Items]
Description of variable rate basis	PRIME
VOEs \| Private Equity Funds
Variable Interest Entity [Line Items]
Revolving lines of credit, capacity	$ 688.0	$ 597.0
Outstanding borrowings	$ 505.0	431.0
VOEs \| Private Equity Funds \| Minimum
Variable Interest Entity [Line Items]
Basis spread	150.00%
VOEs \| Private Equity Funds \| Maximum
Variable Interest Entity [Line Items]
Basis spread	155.00%
VOEs \| LIBOR \| Private Equity Funds
Variable Interest Entity [Line Items]
Description of variable rate basis	LIBOR
VOEs \| EURIBOR \| Private Equity Funds
Variable Interest Entity [Line Items]
Description of variable rate basis	EURIBOR
Nonconsolidated VIEs
Variable Interest Entity [Line Items]
Ownership interest in unconsolidated CLO	$ 321.0	$ 110.0

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: 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(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin.

+ References

No definition available.

+ Details

Name:	us-gaap_LoansReceivableBasisSpreadOnVariableRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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_VariableInterestEntityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net carrying amount of the assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), when the reporting entity is not the VIE's primary beneficiary.

+ References

No definition available.

+ Details

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

- Definition

Default of Collateral Assets, Percentage

+ References

No definition available.

+ Details

Name:	voya_DefaultofCollateralAssetsPercentage
Namespace Prefix:	voya_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Unpaid Principal Exceeds Fair Value, Corporate Loan

+ References

No definition available.

+ Details

Name:	voya_UnpaidPrincipalExceedsFairValueCorporateLoan
Namespace Prefix:	voya_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted Average Maturity, Debt

+ References

No definition available.

+ Details

Name:	voya_WeightedAverageMaturityDebt
Namespace Prefix:	voya_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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

Name:	us-gaap_VariableRateAxis=voya_EuroInterbankOfferedRateEuriborMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=voya_VotingInterestEntityPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_PrivateEquityFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember
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