Earnings Per Share - Computation of Basic and Diluted Earnings Per Share for Continuing Operations (Parenthetical) (Detail) - shares	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Stock Compensation Plan [Member]
Dilutive Securities Included And Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share based awards excluded from the calculation of diluted earnings per share	300,000	500,000	200,000	500,000
Performance Shares [Member]
Dilutive Securities Included And Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share based awards excluded from the calculation of diluted earnings per share	300,000	200,000	300,000	200,000
Exercised / Vested, Number of Shares	0	0	0	0

Dilutive securities included and antidilutive securities excluded from computation of earnings per share.

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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