v3.20.1

Debt - Additional Information (Details) - USD ($)				3 Months Ended
	Mar. 24, 2020	Nov. 18, 2019	May 03, 2019	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Outstanding debt						$ 0
Letters of credit outstanding				$ 31,700,000	$ 31,700,000
Revolving Credit Facility
Debt Instrument [Line Items]
Outstanding debt				68,984,000
Term Loan A Facility
Debt Instrument [Line Items]
Outstanding debt				98,392,000	99,608,000
Credit Agreement
Debt Instrument [Line Items]
Interest expense				600,000
Credit Agreement | Morgan Stanley Senior Funding, Inc | Minimum
Debt Instrument [Line Items]
Adjusted quick ratio			1.00%
Credit Agreement | Morgan Stanley Senior Funding, Inc | Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument term, years			4 years
Maximum borrowing capacity			$ 100,000,000.0
Amount borrowed under debt facility	$ 69,300,000
Credit facility expiration and maturity month and year			2023-02
Letters of credit outstanding				$ 30,700,000	$ 30,700,000
Credit Agreement | Morgan Stanley Senior Funding, Inc | Revolving Credit Facility | Adjusted One-Month LIBOR
Debt Instrument [Line Items]
Debt instrument, applicable margin on variable rate	1.75%
Credit Agreement | Morgan Stanley Senior Funding, Inc | Term Loan A Facility
Debt Instrument [Line Items]
Debt instrument term, years			4 years
Maximum borrowing capacity			$ 100,000,000.0
Amount borrowed under debt facility		$ 100,000,000.0
Debt instrument, amortization description				Loans under the Term Loan A Facility amortize in equal quarterly installments beginning on March 31, 2020, in an aggregate annual amount equal to (i) on or prior to December 31, 2021, 1.25% of the drawn principal amount of the Term Loan Facility or $1.25 million and (ii) thereafter, 2.50% of the drawn principal amount of the Term Loan Facility or $2.5 million, with the remaining balance payable on the maturity date of the Term Loan A Facility in February 2023.
Debt instrument maturity month and year			2023-02
Credit Agreement | Morgan Stanley Senior Funding, Inc | Term Loan A Facility | On or Prior to December 31, 2021
Debt Instrument [Line Items]
Percentage of amortization on drawn principal amount			1.25%
Amortization, aggregate principal amount			$ 1,250,000
Credit Agreement | Morgan Stanley Senior Funding, Inc | Term Loan A Facility | Thereafter December 31, 2021
Debt Instrument [Line Items]
Percentage of amortization on drawn principal amount			2.50%
Amortization, aggregate principal amount			$ 2,500,000
Credit Agreement | Morgan Stanley Senior Funding, Inc | Term Loan A Facility | Adjusted One-Month LIBOR
Debt Instrument [Line Items]
Debt instrument, applicable margin on variable rate		1.75%
Credit Agreement | Morgan Stanley Senior Funding, Inc | Uncommitted Incremental Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 50,000,000.0
Debt to company's EBITDA, description				1.0x of the Company’s EBITDA for the most recently completed four fiscal quarter period
Credit Agreement | Morgan Stanley Senior Funding, Inc | Uncommitted Incremental Facility | Maximum
Debt Instrument [Line Items]
Secured leverage ratio			1.50%

X

- Definition

Debt instrument adjusted quick ratio.

+ References

No definition available.

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- Definition

Debt instrument amortization aggregate principal amount.

+ References

No definition available.

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- Definition

Debt instrument amortization description.

+ References

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- Definition

Debt instrument amortization percentage.

+ References

No definition available.

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- Definition

Debt instrument maturity month and year.

+ References

No definition available.

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- Definition

Debt instrument secured leverage ratio.

+ References

No definition available.

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- Definition

Description of debt to consolidated earnings before interest tax depreciation and amortization ratio.

+ References

No definition available.

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- Definition

Line of credit facility expiration and maturity month and year.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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