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Basis of Presentation and Significant Accounting Policies - Changes in Carrying Amount of Other Non-Current Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deferred Finance Costs [Roll Forward]
Balance at beginning of period	$ 8,006	$ 9,583	$ 4,202
Additions	(6,803)	0	(9,443)
Interest expense	(2,540)	(1,577)	(4,062)
Balance at end of period	12,269	$ 8,006	9,583
Former Credit Facility
Deferred Finance Costs [Roll Forward]
Interest expense	$ (700)		$ (2,400)

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Deferred Finance Costs [Roll Forward]

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Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-Name Accounting Standards Codification
-Topic 220
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-Section S99
-Paragraph 2
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-Topic 835
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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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-Topic 220
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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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