Current weighted average loan to value ratio of commercial mortgage loan.

No definition available.

Name:	hig_CurrentWeightedAverageLoanToValueRatioOfCommercialMortgageLoan
Namespace Prefix:	hig_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of loans with an allowance

+ References

No definition available.

+ Details

Name:	hig_Numberofloanswithanallowance
Namespace Prefix:	hig_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Original weighted average loan to value ratio of commercial mortgage loan.

+ References

No definition available.

+ Details

Name:	hig_OriginalWeightedAverageLoanToValueRatioOfCommercialMortgageLoan
Namespace Prefix:	hig_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of principal due on delinquent mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column H
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column H))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

Name:	srt_MortgageLoansOnRealEstatePrincipalAmountOfDelinquentLoans
Namespace Prefix:	srt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ 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 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_AllowanceForLoanAndLeaseLossesPeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 310
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118959141&loc=d3e21338-158488

+ Details

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

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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

- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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

- Details

Name:	us-gaap_LongLivedAssetsHeldForSaleByAssetTypeAxis=us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ValuationAllowancesAndReservesTypeAxis=us-gaap_AllowanceForLoanAndLeaseLossesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	hig_ValueTypeAxis=hig_AmortizedCostMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_MortgagesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Investments - Investments - Mortgage Loans- Valuation Allowance Activity (Details)	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	$ 3,736,000,000		$ 3,704,000,000
Number of loans with an allowance	0
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ (1,000,000)	$ (1,000,000)
(Additions)/Reversals	1,000,000	0
Deductions	0	0
Ending balance	$ 0	$ (1,000,000)
Current Weighted Average Loan to Value Ratio of Commercial Mortgage Loan	52.00%
Original Weighted Average Loan to Value Ratio of Commercial Mortgage loan	61.00%
Held-for-sale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans with an allowance	0		0
SEC Schedule, 12-09, Allowance, Loan and Lease Loss [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value			$ 23,000,000
Number of loans with an allowance	0
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	$ 3,736,000,000		3,704,000,000
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	(1,000,000)
Ending balance	0
Commercial Loan [Member] \| Mortgage loans
Allowance for Loan and Lease Losses [Roll Forward]
Mortgage loans past due by 90 days or more	0
Amortized Cost [Member] \| Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying Value	$ 3,700,000,000		3,700,000,000
Mortgage loans \| Commercial Loan [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Mortgage loans past due by 90 days or more			$ 0