Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - $ / shares	Feb. 26, 2020	Feb. 05, 2020
Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Maturity date extended, period	2 years
Senior Notes maturity date	Feb. 26, 2023
Class A Common Stock [Member]
Subsequent Event [Line Items]
Dividend declared per share		$ 0.14
Dividend payable declared date		Feb. 05, 2020
Dividend payable, date to be paid		Mar. 11, 2020
Dividend payable record date		Feb. 26, 2020
Class B Common Stock [Member]
Subsequent Event [Line Items]
Dividend declared per share		$ 0.14
Dividend payable declared date		Feb. 05, 2020
Dividend payable, date to be paid		Mar. 11, 2020
Dividend payable record date		Feb. 26, 2020

Debt maturity date extended period.

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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Period Type:	instant

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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