Weighted Average Common Shares - Additional Information (Detail) - shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Stock Option [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive awards excluded from computations of diluted earnings per share	700,000	800,000
Common Stock [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average number of shares issued	16,000	24,000	37,000
Shares repurchased under stock repurchase program	200,000
Common Stock [Member] \| Maximum [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Weighted average number of shares issued	100,000	100,000	100,000

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.

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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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Number of shares issued during the period as a result of an employee stock purchase plan.

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