Short-Term Borrowings (Details) - USD ($)		1 Months Ended	6 Months Ended
	Feb. 08, 2016	Feb. 29, 2016	Jun. 30, 2016	Dec. 31, 2015	Apr. 23, 2015	Feb. 17, 2015	May 30, 2014	Mar. 14, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity			$ 3,200,000
Line of Credit Facility, Maximum Borrowing Capacity			5,000,000
Line of Credit Facility, Amount Outstanding			$ 25,000,000	$ 15,000,000
Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 35,000,000.0							$ 25.0
Line of Credit, Liquidity Threshold	15,000,000.0
Line of Credit, Liquidity Threshold, Last Month of Quarter	20,000,000.0
Line of Credit, Modification Fee	35,000
Debt Instrument, Average Monthly Interest Expense	10,000,000
Line of Credit Facility, Covenant Compliance, Minimum Cash Balance Required, Percent			50.00%
Line of Credit, Facility Fee	$ 52,500
Payment for Facility Fee		$ 48,000
Line of Credit Facility, Commitment Fee Percentage	1.50%
Line of Credit Facility, Covenant Terms, Adjusted Earnings before Interest, Taxes, Depreciation and Amortization, Debt Outstanding Balance Threshold	$ 15,000,000.0
Line of Credit Facility, Covenant Terms, Maximum Restructuring Expense Allowed in First Quarter	1,700,000
Line of Credit Facility, Covenant Terms, Maximum Restructuring Expense Allowed in Second Quarter	1,140,000
Line of Credit Facility, Covenant Terms, Maximum Restructuring Expense Allowed in Third Quarter	1,000,000
Line of Credit Facility, Covenant Terms, Maximum Restructuring Expense Allowed after Third Quarter	$ 0
Line of Credit Facility, Covenant Terms, Minimum Cash Balance Required			$ 4,000,000.0
Convertible Senior Notes [Member] | 2015 Convertible Senior Notes [Member]
Line of Credit Facility [Line Items]
Debt instrument, interest rate, stated percentage						4.50%
Maximum [Member] | 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 [Member] | Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Debt Covenant, Liquidity	$ 10,000,000.0
Line of Credit Facility, Covenant Terms, Adjusted Earnings before Interest, Taxes, Depreciation and Amortization over Debt Outstanding Balance Threshold	10,000,000.0
Line of Credit Facility, Covenant Terms, Adjusted Earnings before Interest, Taxes, Depreciation and Amortization under Debt Outstanding Balance Threshold	$ 7,500,000.0
Minimum [Member] | 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] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					$ 5,000,000.0
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							$ 2,000,000.0
Line of Credit Facility, Current Borrowing Capacity							$ 2,000,000.0	$ 1,000,000.0
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable, Days from Invoice Date			60 days
Geographic Distribution, Domestic [Member] | Trade Accounts Receivable [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%
Geographic Distribution, Foreign [Member] | Maximum [Member] | Trade Accounts Receivable [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable	80.00%
Geographic Distribution, Foreign [Member] | Minimum [Member] | Trade Accounts Receivable [Member] | Line of Credit [Member] | 2014 Debt Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Borrowing Formula, Eligible Accounts Receivable	75.00%