Balance Sheet Information (Details 2) (USD $)	3 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Restricted Cash
Restricted cash		$ 3,448,000	$ 2,017,000
Accounts Receivable, Net
Allowance for doubtful accounts receivable (in dollars)		500,000	500,000
Inventories
Materials		36,499,000	36,523,000
Work in process		19,815,000	13,363,000
Finished goods		7,793,000	9,921,000
Inventories		64,107,000	59,807,000
Cost Method Investment
Total recorded investment		15,300,000	14,500,000
Percentage ownership of preferred shares		15.30%
Percentage ownership of cost method investee		12.00%
Additional cost method investment	800,000
Customer deposits
Customer deposits		27,400,000	32,700,000
Collateral for Bank Guarantees
Restricted Cash
Restricted cash		$ 3,400,000	$ 2,000,000