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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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End date of debt instrument redemption period, in CCYY-MM-DD format.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Long-Term Debt (Redemption of 6.125% Senior Notes and 5.125% Senior Notes) - Additional Information (Detail) - USD ($) $ in Millions		6 Months Ended	12 Months Ended
	Jun. 10, 2020	Jun. 30, 2021	Dec. 31, 2020	Jul. 01, 2014	Mar. 12, 2013
6.125% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		6.125%			6.125%
Debt instrument, redemption date		Jun. 24, 2020
Debt instrument, redemption price percentage of principal amount	100.00%
5.125% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		5.125%		5.125%
Debt instrument, redemption date		Jun. 24, 2020
Debt instrument, redemption price percentage of principal amount	100.00%
6.125% Senior Notes Due 2021 and 5.125% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Debt extinguishment charge			$ 3.3