Short-Term Borrowings (Details) (USD $)	12 Months Ended	0 Months Ended
	Dec. 31, 2014	Mar. 14, 2014	Dec. 31, 2013	Sep. 01, 2014	May 30, 2014	Feb. 17, 2015
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	35,000,000
Line of credit	10,000,000		15,000,000
Line of Credit Facility, Remaining Borrowing Capacity	14,400,000
Convertible Senior Notes [Member] | 2015 Convertible Senior Notes
Line of Credit Facility [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Debt Instrument, Liquidity Threshold, Period Prior to Maturity Date	120 days
Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity		25,000,000.0
Line of Credit, Liquidity Threshold		15,000,000
Line of Credit, Liquidity Threshold, Last Month of Quarter		20,000,000
Line of Credit, Modification Fee		35,000
Line of Credit Facility, Commitment Fee Amount		35,000
Debt Instrument, Average Monthly Interest Expense		10,000,000
Line of Credit Facility, Cancellation Fee Percentage		1.50%
Line of Credit Facility, Covenant Compliance, Minimum Required Balance				4,000,000
Line of Credit Facility, Covenant Compliance, Minimum Cash Required, Percent				50.00%
Line of Credit Facility, Debt Covenant, Liquidity		10,000,000
United States Accounts Receivable Balance [Member] | Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable	80.00%
Foreign Accounts Receivable Balance [Member] | Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable	65.00%
Certain Cases [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable	80.00%
Maximum | Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable past due	60 days
Maximum | Line of Credit [Member] | 2014 Debt Agreement [Member] | Prime Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.25%
Minimum | Line of Credit [Member] | 2014 Debt Agreement [Member] | Prime Rate [Member]
Line of Credit Facility [Line Items]
Debt Instrument, Basis Spread on Variable Rate		0.75%
Letter of Credit [Member] | Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					2,000,000
Line of Credit Facility, Current Borrowing Capacity		2,000,000			1,000,000
Subsequent Event
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity						$ 7,400,000