Fair Value Measurements - Summary of Company's Fair Value Hierarchy for its Financial Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets:
Fair value of investments	$ 23,480	$ 503
Liabilities:
Fair value of liabilities	(508)	(1,144)
Money Market Funds [Member]
Assets:
Fair value of cash equivalents	6,462	503
Interest Rate Swap [Member]
Liabilities:
Fair value of liabilities	(508)	(1,144)
Level 1 [Member]
Assets:
Fair value of investments	6,462	503
Liabilities:
Fair value of liabilities	0	0
Level 1 [Member] \| Money Market Funds [Member]
Assets:
Fair value of cash equivalents	6,462	503
Level 1 [Member] \| Interest Rate Swap [Member]
Liabilities:
Fair value of liabilities	0	0
Level 2 [Member]
Assets:
Fair value of investments	17,018	0
Liabilities:
Fair value of liabilities	(508)	(1,144)
Level 2 [Member] \| Money Market Funds [Member]
Assets:
Fair value of cash equivalents	0	0
Level 2 [Member] \| Interest Rate Swap [Member]
Liabilities:
Fair value of liabilities	(508)	$ (1,144)
Marketable Investments [Member]
Assets:
Fair value of cash equivalents	17,018
Marketable Investments [Member] \| Level 1 [Member]
Assets:
Fair value of cash equivalents	0
Marketable Investments [Member] \| Level 2 [Member]
Assets:
Fair value of cash equivalents	$ 17,018

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313

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- Definition

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

+ References

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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