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Insurance - Recoverables from reinsurance, progression of allowance for expected credit losses (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Jan. 01, 2020
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward] |  |
Beginning balance | $ 18 |
Impact of adoption of new accounting policy | 13 | $ 6
Provision for expected credit losses | 2 |
Write-offs charged against the allowance | 0 |
Businesses disposed | (1) |
Ending balance | 13 |
Property and casualty insurance |  |
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward] |  |
Beginning balance | 18 |
Impact of adoption of new accounting policy | 6 | 11
Provision for expected credit losses | 0 |
Write-offs charged against the allowance | 0 |
Businesses disposed | (1) |
Ending balance | 6 |
Annuity |  |
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward] |  |
Beginning balance | 0 |
Impact of adoption of new accounting policy | 0 | 0
Provision for expected credit losses | 0 |
Write-offs charged against the allowance | 0 |
Businesses disposed | 0 |
Ending balance | 0 |
Other |  |
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward] |  |
Beginning balance | 0 |
Impact of adoption of new accounting policy | 7 | $ (5)
Provision for expected credit losses | 2 |
Write-offs charged against the allowance | 0 |
Businesses disposed | 0 |
Ending balance | $ 7 |

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- Definition Reinsurance recoverable, allowance for credit loss, businesses disposed + References No definition available. + Details
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- Definition Amount of the write-down or write-off of a receivable from a reinsurer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
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- 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
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- Definition Amount of expense (reversal of expense) for expected credit loss on reinsurance recoverable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
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- Definition Amount of allowance for credit loss on reinsurance recoverable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 + Details
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