NET INVESTMENT GAINS (LOSSES) - INSURANCE - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, as of beginning of period	$ 140,252	$ 120,895
Initial impairments for credit losses recognized on securities not previously impaired	186	27,609
Initial credit loss allowance recognized on PCD securities	5,406	5,628
Accretion of initial credit loss allowance on PCD securities	0	321
Reductions due to sales (or maturities, pay downs or prepayments) during the period of securities previously identified as credit impaired	(7,565)	(10,102)
Net additions / reductions for securities previously impaired	(46,633)	(52,705)
Balance, as of end of period	91,646	91,646
Corporate
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, as of beginning of period	0	0
Initial impairments for credit losses recognized on securities not previously impaired	0	0
Initial credit loss allowance recognized on PCD securities	0	0
Accretion of initial credit loss allowance on PCD securities	0	0
Reductions due to sales (or maturities, pay downs or prepayments) during the period of securities previously identified as credit impaired	0	0
Net additions / reductions for securities previously impaired	0	0
Balance, as of end of period	0	0
Structured
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, as of beginning of period	140,252	120,895
Initial impairments for credit losses recognized on securities not previously impaired	186	27,609
Initial credit loss allowance recognized on PCD securities	5,406	5,628
Accretion of initial credit loss allowance on PCD securities	0	321
Reductions due to sales (or maturities, pay downs or prepayments) during the period of securities previously identified as credit impaired	(7,565)	(10,102)
Net additions / reductions for securities previously impaired	(46,633)	(52,705)
Balance, as of end of period	$ 91,646	$ 91,646

Debt Securities, Available-for-sale, Allowance for Credit Loss, Purchased with Credit Deterioration, Accretion

No definition available.

Name:	kkr_DebtSecuritiesAvailableForSaleAllowanceForCreditLossPurchasedWithCreditDeteriorationAccretion
Namespace Prefix:	kkr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

+ Details

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

- Definition

Amount of expense for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), for which no credit loss was previously recorded.

+ References

+ Details

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

- Definition

Amount of expense (reversal of expense) for allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis, with previously recorded allowance.

+ References

+ Details

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

- Definition

Amount of increase in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and beneficial interest, purchased with credit deterioration.

+ References

+ Details

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

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

- Definition

Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale.

+ References

+ Details

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

- Details

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

- Details

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