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Pension and Other Postretirement Benefits (Tables) | 6 Months Ended
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Jun. 30, 2021
Compensation And Retirement Disclosure [Abstract] |
Components of Net Periodic Benefit Cost | The components of net periodic benefit cost were as follows:
|  | Second quarter ended June 30, |  |  | Six months ended June 30, |
Pension benefits |  | 2021 |  |  | 2020 |  |  | 2021 |  |  | 2020 |
Service cost |  | $ | 5 |  |  | $ | 13 |  |  | $ | 10 |  |  | $ | 27 |
Interest cost(1) |  |  | 29 |  |  |  | 41 |  |  |  | 58 |  |  |  | 83 |
Expected return on plan assets(1) |  |  | (73 | ) |  |  | (73 | ) |  |  | (146 | ) |  |  | (147 | )
Recognized net actuarial loss(1) |  |  | 50 |  |  |  | 53 |  |  |  | 101 |  |  |  | 104 |
Settlements(2) |  |  | 39 |  |  |  | — |  |  |  | 39 |  |  |  | — |
Curtailments(2) |  |  | — |  |  |  | 1 |  |  |  | — |  |  |  | 4 |
Net periodic benefit cost |  | $ | 50 |  |  | $ | 35 |  |  | $ | 62 |  |  | $ | 71 |
|  | Second quarter ended June 30, |  |  | Six months ended June 30, |
Other postretirement benefits |  | 2021 |  |  | 2020 |  |  | 2021 |  |  | 2020 |
Service cost |  | $ | 1 |  |  | $ | 1 |  |  | $ | 3 |  |  | $ | 2 |
Interest cost(1) |  |  | 4 |  |  |  | 5 |  |  |  | 8 |  |  |  | 10 |
Recognized net actuarial loss(1) |  |  | 5 |  |  |  | 5 |  |  |  | 11 |  |  |  | 9 |
Amortization of prior service benefit(1) |  |  | (4 | ) |  |  | (4 | ) |  |  | (8 | ) |  |  | (7 | )
Settlements(2) |  |  | — |  |  |  | — |  |  |  | 26 |  |  |  | — |
Curtailments(2) |  |  | — |  |  |  | (2 | ) |  |  | (17 | ) |  |  | (2 | )
Net periodic benefit cost |  | $ | 6 |  |  | $ | 5 |  |  | $ | 23 |  |  | $ | 12 |
(1) | These amounts were reported in Other (income) expenses, net on the accompanying Statement of Consolidated Operations (see Note Q).
(2) | These amounts were reported in Restructuring and other charges, net on the accompanying Statements of Consolidated Operations (see Note D) and of Cash Flows.
Summary of Information in Curtailment or Settlement of Benefits Requiring Remeasurement, Update to Discount Rates Used to Determine Benefit Obligations of Affected Plans | The following table presents certain information and the financial impacts of this action on the accompanying Consolidated Financial Statements:
Action # |  | Number of affected plan participants |  | Weighted average discount rate as of December 31, 2020 |  |  | Plan remeasurement date |  | Weighted average discount rate as of plan remeasurement date |  |  | Decrease to accrued pension benefits liability |  |  | Decrease to accrued other postretirement benefits liability |  |  | Curtailment gain(1) |  |  | Settlement charge(1) |
1 |  | ~840 |  | 2.45% |  |  | March 31, 2021 |  | 3.06% |  |  | $ | — |  |  | $ | (106 | ) |  | $ | (17 | ) |  | $ | 26 |
2 |  | ~120 |  | 2.38% |  |  | June 30, 2021 |  | 2.71% |  |  | $ | (90 | ) |  | $ | — |  |  | $ | — |  |  | $ | 39 |
(1) | These amounts represent the accelerated amortization of a portion of the existing prior service benefit for curtailments and net actuarial loss for settlements and were reclassified from Accumulated other comprehensive loss to Restructuring and other charges, net (see Note D) on the accompanying Statement of Consolidated Operations.

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- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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