Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration (in years)	10 years
Weighted-average grant date fair values of awards granted	$ 3.75	$ 7.11	$ 5.61
Intrinsic value of awards exercised	$ 0	$ 100,000	$ 0
Fair value of awards vested	100,000	700,000	1,200,000
Time-vesting RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards vested	$ 1,900,000	$ 1,900,000	$ 1,100,000
Number of Equity Instruments Awarded in Period	310,700	135,759	276,085
Time-vesting RSUs [Member] \| Two Years from the Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of RSUs vesting	50.00%
Time-vesting RSUs [Member] \| Three Year from the Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of RSUs vesting	50.00%
Performance-Vesting RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards vested	$ 2,300,000	$ 2,500,000	$ 300,000
Number of Equity Instruments Awarded in Period	190,634	194,563	370,616
Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost recognized for awards under the Equity Plan	$ 6,200,000	$ 6,800,000	$ 8,700,000
Tax benefits recognized	500,000	$ 800,000	$ 2,600,000
Unrecognized compensation cost related to nonvested awards under the Equity Plan	$ 6,600,000
Expected weighted average period to recognized compensation cost related to nonvested awards under the Equity Plan	2 years
Equity Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock available for issuance	7,500,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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 authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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