Fair Value Measurements Narrative (Details) - USD ($) $ in Thousands	6 Months Ended	9 Months Ended
	Jun. 30, 2014	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Line of Credit Facility, Fair Value of Amount Outstanding					$ 66,100
Carrying value of the line of credit				$ 0	66,100
Forward Contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative, Notional Amount		$ 0			3,080
Gain (Losses) as a result of changes in the fair value of the contracts	$ (288)	$ (49)	$ (852)
Derivative Asset, Fair Value, Gross Asset				0	0
Senior Secured Term Loan Credit Facilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Payable				99,500	0
Senior Secured Term Loan Credit Facilities [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans Payable, Fair Value Disclosure				99,500
Convertible Notes Due in 2017 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of convertible notes				41	57,500
Convertible Notes Due in 2017 [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible Debt, Fair Value Disclosures				25	21,966
Senior Secured Notes Due in 2016 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior Notes, Carrying Value					210,000
Carrying value of senior secured notes				0	6,681
Senior Secured Notes Due in 2016 [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Fair Value Disclosure					160,662
Senior Secured Notes Due in 2018 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of senior secured notes				177,019	203,319
Senior Secured Notes Due in 2018 [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument, Fair Value Disclosure				116,833
Convertible Notes Due in 2019 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of convertible notes				22,323	$ 0
Convertible Notes Due in 2019 [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible Debt, Fair Value Disclosures				$ 5,369