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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Contractual interest rate for funds borrowed, under the debt agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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Borrowing Arrangements - Additional Information (Detail)	1 Months Ended	6 Months Ended
	Jul. 31, 2015 EUR (€)	Jun. 30, 2017 USD ($)	Jun. 30, 2017 EUR (€)	Sep. 30, 2015 USD ($)
Debt Instrument [Line Items]
Debt Instrument, covenant description		The Company is required to maintain certain financial covenants including a consolidated charge coverage ratio (as defined in the Credit Agreement) of at least 1.25 to 1.00, a consolidated leverage ratio (as defined in the Credit Agreement) no greater than 3.5 to 1.00 and a minimum cash balance of $35.0 million at the end of each quarter. The Company was in compliance with all covenants for the quarter ended June 30, 2017.
Percentage of excess cash flow used for annual debt payment condition one		33.00%
Term loan principal amount outstanding condition one		$ 20,000,000
Percentage of excess cash flow used for annual debt payment condition two		25.00%
Minimum [Member]
Debt Instrument [Line Items]
Charge coverage ratio for the next fiscal year		1.25%
Required cash balance		$ 35,000,000
Term loan principal amount outstanding condition two		10,000,000
Maximum [Member]
Debt Instrument [Line Items]
Term loan principal amount outstanding condition two		$ 20,000,000
First Quarter [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Consolidated leverage ratio for first quarter of next fiscal year		3.50%
U.S. Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding amounts		$ 16,200,000
Base rate interest		3.79%
U.S. Term Loan Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative instrument, notional amount				$ 20,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Outstanding amounts		$ 39,900,000
Borrowing capacity under credit facility		40,000,000
U.S. Term Loan And Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs		200,000
Credit Agreement [Member] \| U.S. Term Loan Credit Facility [Member]
Debt Instrument [Line Items]
Outstanding amounts		$ 16,200,000
Credit Agreement [Member] \| U.S. Term Loan Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate		1.04%
Derivative instrument, notional amount		$ 10,900,000
Debt instrument LIBOR rate				0.99%
Debt instrument interest rate		3.74%	3.74%
Credit Agreement [Member] \| Revolving Credit Facility
Debt Instrument [Line Items]
Base rate interest		4.25%
Credit Agreement [Member] \| U.S. [Member]
Debt Instrument [Line Items]
Credit facility expiration date		Feb. 02, 2019
Credit Agreement [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Credit facility expiration date		Mar. 31, 2020
Credit Agreement [Member] \| Czech Republic [Member] \| Miconex [Member]
Debt Instrument [Line Items]
Debt Instrument, covenant description		The credit agreement requires Miconex to maintain certain financial covenants, including a debt-to-earnings-before-interest-depreciation-and-amortization ratio no greater than 3.00 to 1.00 and an equity ratio of at least 15%. As of June 30, 2017, Miconex was in compliance with all of its covenants.
Debt to earnings before interest depreciation and amortization ratio maximum	300.00%
Equity ratio minimum	15.00%
Bank Debt [Member]
Debt Instrument [Line Items]
Outstanding amount of borrowing classified as long-term debt		$ 60,800,000
Bank Debt [Member] \| U.S. [Member] \| Revolving Credit Facility
Debt Instrument [Line Items]
Available borrowings under revolving loan		$ 100,000
Bank Debt [Member] \| Czech Republic [Member]
Debt Instrument [Line Items]
Debt due date, start year		2017
Debt due date, end year		2020
Bank Debt [Member] \| Czech Republic [Member] \| Miconex [Member]
Debt Instrument [Line Items]
Outstanding amounts		$ 4,900,000
Bank Debt [Member] \| Czech Republic [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		1.30%	1.30%
Bank Debt [Member] \| Czech Republic [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument interest rate		2.30%	2.30%
Bank Debt [Member] \| Czech Republic [Member] \| U.S. Term Loan Credit Facility [Member] \| Miconex [Member]
Debt Instrument [Line Items]
Outstanding amounts		$ 400,000	€ 400,000
Borrowing capacity under credit facility \| €	€ 800,000
Bank Debt [Member] \| Czech Republic [Member] \| Revolving Credit Facility
Debt Instrument [Line Items]
Available borrowings under revolving loan		4,900,000	4,300,000
Bank Debt [Member] \| Czech Republic [Member] \| Revolving Credit Facility \| Miconex [Member]
Debt Instrument [Line Items]
Outstanding amounts		$ 4,500,000	€ 4,000,000
Bank Debt [Member] \| Czech Republic [Member] \| Revolving Credit Facility \| Maximum [Member] \| Miconex [Member]
Debt Instrument [Line Items]
Borrowing capacity under credit facility \| €	€ 8,300,000