Convertible Senior Secured Notes (Details) (USD $)	1 Months Ended	3 Months Ended	6 Months Ended
	May 31, 2013	Jun. 30, 2013	Jun. 30, 2013 D item	Jun. 30, 2012	May 03, 2013
Notes payable
Aggregate principal amount of convertible senior secured notes issued	$ 90,000,000	$ 90,000,000
Fixed interest rate (as a percent)	7.50%	7.50%	7.50%
Debt Instrument, Unamortized Discount		2,500,000	2,500,000		3,000,000
Deferred Offering Costs		3,500,000	3,500,000
Net proceeds from issuance of debt		86,500,000	90,000,000
Repayments of Secured Debt		19,600,000	24,344,000	1,771,000
Number of trading days			5
Consecutive trading day period			5 days
Conversion rate, number of shares			188.7059
Conversion rate, principal amount			1,000
Initial conversion price per share of Common Stock			$ 5.30
Discount rate		2.00%	2.00%
Price require to pay for note			100.00%
Debt financing costs			3,500,000
Financing costs capitalized		2,600,000	2,600,000
Financing costs adjusted to APIC			900,000
Debt discount		2,500,000	2,500,000		3,000,000
Current [Member]
Notes payable
Debt Instrument, Unamortized Discount		400,000	400,000
Debt discount		400,000	400,000
Noncurrent [Member]
Notes payable
Debt Instrument, Unamortized Discount		2,100,000	2,100,000
Debt discount		2,100,000	2,100,000
During 30 Consecutive Trading Day Period [Member]
Notes payable
Number of trading days			20
Within Five Trading Days Prior To Conversion Date [Member]
Notes payable
Consecutive trading day period			30 days
Immediately Following Any Five Consecutive Trading Day Period [Member]
Notes payable
Consecutive business day period			5 days
Minimum
Notes payable
Consent of percentage of holders of aggregate principal amount of notes outstanding and affected			66.667%
Number of calendar days, after the date on which a fundamental change notice is delivered, the company has to purchase Notes, if required by holders			20 days
Maximum
Notes payable
Percentage of product greater than amount of Notes			98.00%
Conversion rate, number of shares			221.7294
Conversion rate, principal amount			$ 1,000
Number of calendar days, after the date on which a fundamental change notice is delivered, the company has to purchase Notes, if required by holders			35 days
On Or After November 1, 2013 [Member]
Notes payable
Number of trading days			5
On Or After November 1, 2013 [Member] | During 30 Consecutive Trading Day Period [Member]
Notes payable
Number of trading days			20
On Or After November 1, 2013 [Member] | Within Five Trading Days Prior To Conversion Date [Member]
Notes payable
Consecutive trading day period			30 days
On Or After May 1, 2017 [Member]
Notes payable
Percentage of applicable conversion price, equal to or exceeded by last reported sale price of common stock, Notes may be redeemed			140.00%
Percentage of the principal amount of Notes to be redeemed equal to the redemption price			100.00%
On Or After May 1, 2017 [Member] | During 30 Consecutive Trading Day Period [Member]
Notes payable
Number of trading days			20
On Or After May 1, 2017 [Member] | Ending On Trading Day Immediately Prior To Date Written Notice Of Redemption Is Delivered [Member]
Notes payable
Consecutive trading day period			30 days