Long-Term Debt (6.500% Senior Notes due 2024) - Additional Information (Detail) - 6.500% Senior Notes Due 2024 [Member] - USD ($)		3 Months Ended
Feb. 16, 2016	Mar. 31, 2022
Debt Instrument [Line Items]
Issued Senior Notes	$ 390,000,000.0
Debt instrument interest rate	6.50%
Debt instrument maturity date	Mar. 01, 2024
Interest on the notes		payable semi-annually in arrears on March 1 and September 1 of each year, beginning on September 1, 2016
Debt instrument, redemption date		Mar. 01, 2021

Face (par) amount of debt instrument at time of issuance.

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Description of the frequency of periodic payments (monthly, quarterly, annual).

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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End date of debt instrument redemption period, in YYYY-MM-DD format.

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