Senior Debt - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 03, 2015	Dec. 31, 2014
Line Of Credit Facility [Line Items]
Prepayment of outstanding debt	$ 31,300,000
Long-term debt, principal payment 2017	8,800,000
Long-term debt, principal payment 2018	9,800,000
Long-term debt, principal payment 2019	11,600,000
Long-term debt, principal payment 2020	$ 96,100,000
Increased credit facility commitment for either revolving credit facility or term loan facility				$ 50,000,000
Weighted average interest rate on outstanding borrowings	3.26%	3.42%
Interest rate swap, fair value	$ 200,000	$ 400,000
Changes in fair value income (loss)	$ 500,000	400,000
Maximum consolidated leverage ratio	375.00%
Minimum fixed charge coverage ratio	125.00%
Increased interest rate of loan due to default	2.00%
Decrease in consolidated leverage ratio in next twelve months	350.00%
Decrease in consolidated leverage ratio in year two	300.00%
Decrease in consolidated leverage ratio thereafter	300.00%
ING Bank N.V. ("Aarding") [Member]
Line Of Credit Facility [Line Items]
Total borrowing capacity	$ 13,700,000
Maximum debt as proportion of EBITDA	3.00%
ING Bank N.V. ("Aarding") [Member] | Bank Overdrafts [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	$ 0	$ 5,300,000
Weighted average interest rate on outstanding borrowings	1.95%	1.95%
Total borrowing capacity	$ 6,300,000
Debt instrument variable interest rate description	Three months Euribor plus 195 basis points	Three months Euribor plus 195 basis points
Minimum [Member] | ING Bank N.V. ("Aarding") [Member]
Line Of Credit Facility [Line Items]
Borrowers solvency ratio	30.00%
Cross Currency Interest Rate Contract [Member] | Minimum [Member]
Line Of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Cross Currency Interest Rate Contract [Member] | Maximum [Member]
Line Of Credit Facility [Line Items]
Basis spread on variable rate	3.00%
Federal Funds Rate [Member]
Line Of Credit Facility [Line Items]
Basis spread on variable rate	0.50%
One-Month LIBOR [Member]
Line Of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Base Rate [Member] | Minimum [Member]
Line Of Credit Facility [Line Items]
Basis spread on variable rate	1.00%
Base Rate [Member] | Maximum [Member]
Line Of Credit Facility [Line Items]
Basis spread on variable rate	2.00%
Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Unused credit availability under credit facility	$ 62,000,000	$ 56,600,000
Debenture Agreement [Member] | Germany [Member]
Line Of Credit Facility [Line Items]
Cash deposit	900,000	700,000
Term Loan [Member]
Line Of Credit Facility [Line Items]
Increased credit facility commitment for either revolving credit facility or term loan facility			$ 170,000,000	35,000,000
U.S. Dollar Revolving Loans [Member]
Line Of Credit Facility [Line Items]
Increased credit facility commitment for either revolving credit facility or term loan facility				$ 15,000,000
Decreased credit facility commitment for either revolving credit facility or term loan facility			$ 60,500,000
Letters of Credit [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	18,000,000	15,400,000
Bank Guarantee Facility [Member] | Singapore [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	1,700,000	1,500,000
Cash deposit	300,000	500,000
Bank Guarantee Facility [Member] | ING Bank N.V. ("Aarding") [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	$ 5,300,000	$ 6,600,000
Weighted average interest rate on outstanding borrowings	2.65%	2.65%
Total borrowing capacity	$ 7,400,000
Debt instrument variable interest rate description	Three months Euribor plus 265 basis points	Three months Euribor plus 265 basis points
China Facility [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	$ 1,300,000	$ 1,400,000
Total borrowing capacity	$ 4,300,000	4,500,000
Interest rate	4.79%
Debt instrument maturity period	2017-02
Letter Of Credit And Bank Guarantees [Member] | Debenture Agreement [Member] | United Kingdom [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	$ 9,000,000	9,000,000
Outstanding stand-by letters of credit and bank guarantees	6,200,000	5,800,000
Letter Of Credit And Bank Guarantees [Member] | Debenture Agreement [Member] | Germany [Member]
Line Of Credit Facility [Line Items]
Aggregate principal amount outstanding under the credit facilities	900,000	1,200,000
Outstanding stand-by letters of credit and bank guarantees	$ 900,000	$ 1,200,000