Debt - Additional Information (Detail) - Secured Credit Agreement [Member] - JPMorgan Chase Bank, N.A. [Member]	9 Months Ended
Sep. 30, 2017 USD ($)
Debt Instrument [Line Items]
Covenant terms, description	The Credit Agreement contains a number of covenants that, among other things, restrict, subject to certain exceptions, the Company’s ability to incur additional indebtedness; create liens on assets; make investments, loans, advances or acquisitions; pay dividends or other distributions; redeem or repurchase certain equity interests; guarantee the obligations of others; and change the business conducted by the Company.
Minimum liquidity, amount	$ 20,000,000
Minimum debt service coverage ratio	130.00%
Maximum leverage ratio	300.00%
Covenant compliance, description	At September 30, 2017, the Company was in compliance with all such covenants.
Term Loan A [Member]
Debt Instrument [Line Items]
Amount available under secured credit agreement	$ 50,000,000
Quarterly principal payments on Term Loan A in 2017, 2018 and March 2019	$ 2,500,000
Maturity date	Apr. 18, 2019
Frequency of periodic payment	Quarterly
Ancillary Facility [Member]
Debt Instrument [Line Items]
Amount available under secured credit agreement	$ 4,000,000
Prime Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.50%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Amount available under secured credit agreement	$ 60,000,000
Carrying value of debt under secured credit agreement	42,000,000
Amount available for future borrowing	$ 18,000,000
Termination date	2019-04
Commitment fees on unused portion of the Revolving Credit Facility	0.25%
Revolving Credit Facility [Member] \| Swingline Subfacility and Letter of Credit Subfacility [Member]
Debt Instrument [Line Items]
Amount available under secured credit agreement	$ 5,000,000
Letter of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Letter of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%

Line of credit facility expiration month year.

No definition available.

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- Definition

Maximum leverage ratio.

+ References

No definition available.

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- Definition

Minimum debt service coverage ratio.

+ References

No definition available.

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- Definition

Minimum liquidity, amount.

+ 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

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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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

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

+ References

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- Definition

Amount of the required periodic payments applied to principal.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Identification of whether the entity has been in compliance with any credit facility debt covenants during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644

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- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

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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.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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