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Earnings Per Share - Additional Information (Detail) - $ / shares shares in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities	2		2
Weighted average exercise price of options	$ 26.45	$ 44.11	$ 26.45
Stock Awards and Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities	6		6
Common shares equivalents that would have been included in diluted average shares outstanding	1		1
Maximum [Member] | Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities		1

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Shares that would have been included in diluted earnings per share calculation.

+ References

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- Definition

Weighted average exercise price of underwater options.

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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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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