v3.20.2

Pension and Other Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2020

Retirement Benefits [Abstract]

Schedule of Expenses Related to Pension and Other Postretirement Benefits

The following table summarizes the total expenses (excluding settlements and curtailments) recognized by Arconic Corporation related to the pension and other postretirement benefits described above:

​			​			​						Pension benefits																								Other postretirement benefits
​			​			​						Third quarter ended September 30,												Nine months ended September 30,												Third quarter ended September 30,												Nine months ended September 30,
Type of Plan			​			Type of Expense						2020			​			2019						2020			​			2019						2020			​			2019						2020			​			2019
Cumulative Direct Plans			​			Net periodic benefit cost						$	22					$	1					$	61					$	4					$	5					$	—					$	17					$	—
Shared Plans			​			Multiemployer contribution						—						16						—						46						—						4						—						15
Shared Plans			​			Cost allocation						—						5						(1)						15						—						2						—						4
​			​			​						$	22					$	22					$	60					$	65					$	5					$	6					$	17					$	19

Schedule of Components of Net Periodic Benefit Cost Classified as Direct Plans

The components of net periodic benefit cost for defined benefit plans classified as Cumulative Direct Plans were as follows:

						Third quarter ended September 30,												Nine months ended September 30,
						2020			​			2019			​			2020			​			2019
Pension benefits
Service cost						$	6					$	1					$	16					$	2
Interest cost						27						1						81						3
Expected return on plan assets						(42)						(2)						(127)						(4)
Recognized net actuarial loss						31						1						92						3
Amortization of prior service benefit						—						—						(1)						—
Settlement						3						—						58						—
Net periodic benefit cost*						$	25					$	1					$	119					$	4
Other postretirement benefits
Service cost						$	1					$	—					$	3					$	—
Interest cost						2						—						10						—
Recognized net actuarial loss						3						—						6						—
Amortization of prior service benefit						(1)						—						(2)						—
Net periodic benefit cost*						$	5					$	—					$	17					$	—

​

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*    Service cost was included within Cost of goods sold, Settlement was included within Restructuring and other charges, and all other components were included in Other expenses (income), net on the accompanying Statement of Consolidated Operations.

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Schedule of Expenses Related to Pension and Other Postretirement Benefits [Table Text Block]

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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)
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