Credit Facility (Details) (USD $)	6 Months Ended											3 Months Ended		6 Months Ended				1 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended			3 Months Ended			6 Months Ended
	Jun. 30, 2011	Jun. 02, 2011	Dec. 31, 2010	Jun. 30, 2011 Wells Fargo Foreign Exchange Facility [Member]	Jun. 30, 2011 Wells Fargo Foreign Exchange Facility [Member] Letter Of Credit [Member]	Jun. 30, 2011 Bank of Montreal Facility [Member]	Dec. 31, 2010 Bank of Montreal Facility [Member]	Jun. 30, 2011 Bank of Montreal Facility [Member] Letter Of Credit And APG [Member]	Dec. 31, 2010 Bank of Montreal Facility [Member] Letter Of Credit And APG [Member]	Dec. 31, 2010 Prior Credit Facility [Member]	Nov. 16, 2009 Prior Credit Facility [Member]	Jun. 30, 2011 Prior Credit Facility [Member] Revolving [Loan Member]	Jun. 30, 2010 Prior Credit Facility [Member] Revolving [Loan Member]	Jun. 30, 2011 Prior Credit Facility [Member] Revolving [Loan Member]	Jun. 30, 2010 Prior Credit Facility [Member] Revolving [Loan Member]	Jun. 30, 2011 Prior Credit Facility [Member] Term Loan [Member]	Dec. 31, 2010 Prior Credit Facility [Member] Term Loan [Member]	Jun. 30, 2011 Credit Facility [Member]	Jun. 30, 2011 Credit Facility [Member] Revolving Asset Based Loans [Member]	Jun. 30, 2011 Credit Facility [Member] Revolving Asset Based Loans [Member]	Jun. 30, 2011 Credit Facility [Member] Revolving Term Loan [Member]	Jun. 30, 2011 Credit Facility [Member] Revolving Term Loan [Member]	Dec. 31, 2010 Credit Facility [Member] Revolving Term Loan [Member]	Jun. 30, 2011 Revolving Asset Based Loans [Member]	Jun. 30, 2011 Revolving Asset Based Loans [Member]	Jun. 02, 2011 Revolving Asset Based Loans [Member]	Jun. 02, 2011 Letter Of Credit [Member]	Jun. 30, 2011 Revolving [Loan Member]	Jun. 30, 2011 Term Loan [Member]	Jun. 30, 2010 Term Loan [Member]	Jun. 30, 2011 Term Loan [Member]	Jun. 30, 2010 Term Loan [Member]	Jun. 02, 2011 Term Loan [Member]
Bank indebtedness
Bank indebtedness (note 7)	$ 34,583,000		$ 17,500,000													$ 0	$ 17,500,000				$ 34,583,000	$ 34,583,000	$ 0
Credit Facility (Textuals) [Abstract]
Maximum borrowing capacity		110,000,000								25,400,000	75,000,000															50,000,000	20,000,000						60,000,000
Maximum aggregate borrowings																								lesser of $50.0 million, and a collateral calculation based on the percentages of the book values of certain of the Company’s net investment in sales-type leases, financing receivables, certain trade accounts receivable, finished goods inventory allocated to backlog contracts and the appraised values of the expected future cash flows related to operating leases and the Company’s owned real property, reduced by certain accruals and accounts payable and subject to other conditions, limitations and reserve right requirements.	lesser of $50.0 million, and a collateral calculation based on the percentages of the book values of certain of the Company’s net investment in sales-type leases, financing receivables, certain trade accounts receivable, finished goods inventory allocated to backlog contracts and the appraised values of the expected future cash flows related to operating leases and the Company’s owned real property, reduced by certain accruals and accounts payable and subject to other conditions, limitations and reserve right requirements.
Effective interest rate												2.97%	4.50%	2.97%	3.56%									2.19%	2.19%				4.03%	4.04%	4.04%	4.03%
Revolving portion of the credit facility																			Wells Fargo’s prime rate plus a margin of 0.50% Per annum	Wells Fargo’s prime rate plus a margin of 0.50% Per annum	Wells Fargo’s prime rate plus a margin of 0.50% Per annum	Wells Fargo’s prime rate plus a margin of 0.50% Per annum						LIBOR plus a margin of 2.00% per annum
Actual Excess Availability	49,200,000																	5,000,000
Line of Credit Facility, Remaining Borrowing Capacity	69,600,000		40,000,000			10,000,000	10,000,000
Amounts drawn	34,583,000		17,500,000					1,200,000	2,400,000												29,600,000	29,600,000						0
Line of credit facility, decrease, repayments														15,000,000		14,600,000
Additional borrowing under revolving term loan																		5,000,000
Current borrowing capacity																	40,000,000		44,200,000	44,200,000
Letters of credit and advance payment guarantees	0
Notional Amount for which arrangements can be entered				50,000,000
Credit limit to cover settlement risk on foreign currency forward contract					10,000,000
Remaining notional value				39,000,000
Settlement risk on its foreign currency forward contracts				0
Minimum cash and excess availability	72,400,000																	15,000,000
Minimum excess availability reserve	5,000,000
Additional Credit Facility (Textuals) [Abstract]
Line of credit facility covenant terms	The Credit Facility provides that the Company will be required to maintain a ratio of funded debt (as defined in the Credit Agreement) to EBITDA (as defined in the Credit Agreement) of not more than 2:1. The Company will also be required to maintain a Fixed Charge Coverage Ratio (as defined in the Credit Agreement) of not less than 1.1:1.0. At all times under the terms of the Credit Facility, the Company is required to maintain minimum Excess Availability of not less than $5.0 million and minimum Cash and Excess Availability of not less than $15.0 million. These amounts were $49.2 million and $72.4 million at June 30, 2011 respectively. The Company was in compliance with all of these requirements at June 30, 2011.
Outstanding borrowings	69,600,000		40,000,000			10,000,000	10,000,000
Amounts drawn under credit facility	$ 34,583,000		$ 17,500,000													$ 0	$ 17,500,000				$ 34,583,000	$ 34,583,000	$ 0