Debt (Loan and Security Agreements) (Details)		12 Months Ended
	May 14, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Nov. 15, 2016 USD ($)
Debt Instrument [Line Items]
Write off of deferred financing costs		$ 100,000	$ 200,000	$ 400,000
Domestic Line of Credit [Member] | Line of Credit [Member] | Base Rate [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	3.00%
Domestic Line of Credit [Member] | Line of Credit [Member] | Base Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	4.00%
Domestic Line of Credit [Member] | Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Variable rate (as a percent)	1.00%
Domestic Line of Credit [Member] | Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	4.00%
Domestic Line of Credit [Member] | Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	5.00%
Domestic Line of Credit [Member] | Line of Credit [Member] | Federal Funds Effective Swap Rate [Member]
Debt Instrument [Line Items]
Variable rate (as a percent)	0.50%
Domestic Line of Credit [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term line of credit		0
Domestic Line of Credit [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Long-term line of credit		43,800,000
Foreign Line of Credit [Member] | Line of Credit [Member] | Base Rate [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	3.00%
Foreign Line of Credit [Member] | Line of Credit [Member] | Base Rate [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	4.00%
Foreign Line of Credit [Member] | Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	4.00%
Foreign Line of Credit [Member] | Line of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (as a percent)	5.00%
Foreign Line of Credit [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term line of credit		0
Foreign Line of Credit [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Long-term line of credit		$ 5,600,000
Credit Agreement [Member]
Debt Instrument [Line Items]
Interest charges (as a percent)		5.70%
Financing costs		$ 1,900,000
Credit Agreement [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 90,000,000
Additional borrowing capacity upon satisfaction of loan covenants					20,000,000
Maximum stock repurchase capacity		$ 8,300,000
Credit Agreement [Member] | Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity					10,000,000
Periodic payment of principal (as a percent)	5.00%
Credit Agreement [Member] | Revolving Credit Facility [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000.0
Multiplier used to calculate borrowing capacity (as a percent)		1
Credit Agreement [Member] | Domestic Line of Credit [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000.0
Credit Agreement [Member] | Domestic Line of Credit [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity					9,000,000
Credit Agreement [Member] | Domestic Line of Credit [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity					44,400,000
Periodic payment of principal (as a percent)	5.00%
Credit Agreement [Member] | Foreign Line of Credit [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 250,000.00
Credit Agreement [Member] | Foreign Line of Credit [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity					1,000,000
Credit Agreement [Member] | Foreign Line of Credit [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 5,600,000
Credit Agreement [Member] | Unsecured Debt [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 16,700,000
Loan Facility [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Increase in interest rate upon default (as a percent)	2.00%
Stock repurchases minimum liquidity requirement	$ 20,000,000.0
U.S. Comerica Agreement and the Canadian Comerica Agreement [Member]
Debt Instrument [Line Items]
Write off of deferred financing costs			$ 100,000