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Intangible Assets - Summary and Other (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2013	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Composition of intangible assets
Total gross amount		$ 17,841	$ 18,024
Accumulated amortization		$ (17,841)	(14,877)
Total			$ 3,147
Useful life/amortization period		60 months	60 months
GMP royalty buyout
Composition of intangible assets
Total gross amount		$ 17,500	$ 17,500
Non-compete agreements
Composition of intangible assets
Total gross amount		341	524
Amortization expense		200	300
Non-compete agreements \| Minimum
Composition of intangible assets
Useful life/amortization period					1 year
Non-compete agreements \| Maximum
Composition of intangible assets
Useful life/amortization period					2 years
Buy-out Agreement with GMP \| GMP royalty buyout
Composition of intangible assets
Useful life/amortization period	5 years
Amortization expense		$ 3,000	$ 3,500	$ 3,500
Notes Payable \| Buy-out Agreement with GMP \| GMP Note Parties
Composition of intangible assets
Face amount at time of issuance	$ 17,500