Notes Payable to Noncontrolling Interest Owners (Narrative) (Details) - USD ($) $ in Thousands						9 Months Ended
	Mar. 09, 2015	Nov. 27, 2014	Oct. 30, 2014	Sep. 29, 2014	Aug. 28, 2014	Sep. 30, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Notes payable to noncontrolling interest owners							$ 13,709
Accrued interest paid						$ 615
Vinccler [Member]
Related Party Transaction [Line Items]
Notes payable to noncontrolling interest owners							6,100
Notes payable maturity date						Dec. 31, 2015
Related party debt forgiven	$ 6,200
London Interbank Offered Rate (LIBOR) [Member] | Vinccler [Member]
Related Party Transaction [Line Items]
Variable spread on reference rate						0.50%
Petroandina [Member]
Related Party Transaction [Line Items]
Notes payable to noncontrolling interest owners							$ 7,600
Notes payable maturity date						Jan. 01, 2016
Debt extension term						1 month
SPA, maximum allowed borrowing per extension					$ 2,000
Short-term borrowings		$ 1,600	$ 2,000	$ 2,000
Commencement date of quarterly interest payment						Dec. 31, 2014
Interest rate						11.00%
Repayment of notes payable						$ 7,600
Accrued interest paid						$ 400