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Earnings Per Share (Narrative) (Detail) - shares shares in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Shares [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0.9	0.9

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- References

No definition available.

+ Details

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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