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Benefit Plans (Summary of non-service cost (benefit) in the condensed consolidated statements of operations (Details) - Pension Plan - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
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Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic defined benefits expense (reversal of expense), excluding service cost component | $ 3 | $ (14) | $ 6 | $ (28)
Insurance claims and policyholder's benefits |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic defined benefits expense (reversal of expense), excluding service cost component | 0 | (4) | 1 | (8)
Other operating expenses |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |
Net periodic defined benefits expense (reversal of expense), excluding service cost component | $ 3 | $ (10) | $ 5 | $ (20)

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- Definition Amount of expense (reversal of expense) for net periodic benefit cost components, excluding service cost component, of defined benefit plan. Amount includes, but is not limited to, interest cost, expected (return) loss on plan asset, amortization of prior service cost (credit), amortization of (gain) loss, amortization of transition (asset) obligation, settlement (gain) loss, curtailment (gain) loss and certain termination benefits. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A + Details
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