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Components of Net Periodic Benefit Cost (Tables)

3 Months Ended

Mar. 31, 2021

Components of net periodic benefit cost [Abstract]

Schedule of net periodic benefit cost

			Pension Benefits
			Three months ended March 31,
			2021						2020
Service cost			$	1.4					$	1.3
Interest cost			2.4						2.8
Expected return on plan assets			(5.5)						(5.1)
Amortization of prior service costs			0.0						0.0
Amortization of net loss			1.5						1.5
Net periodic benefit cost			$	(0.2)					$	0.5

			Other Postretirement Benefits ("OPEB")
			Three months ended March 31,
			2021						2020
Service cost			$	0.1					$	0.1
Interest cost			0.6						0.8
Amortization of prior service cost			(0.8)						(0.8)
Amortization of net loss			0.6						1.0
Net periodic benefit cost			$	0.5					$	1.1

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- Definition

Components of net periodic benefit cost [Abstract]

+ References

No definition available.

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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

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