Derivative instruments (Tables)

6 Months Ended

Jun. 30, 2014

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Fair Values of Derivative Instruments

The tables below disclose the types of derivative instruments the Company owns, the classifications and fair values of these instruments within the balance sheet, and the amount of gain (loss) recognized in other comprehensive income (loss) (“OCI”) or net income (loss).

(U.S. Dollars, in thousands) As of June 30, 2014	Fair value: favorable (unfavorable)			Balance sheet location
Cross-currency swap	$	(863	)		Other long-term liabilities
Warrants	$	107			Other long-term assets
As of December 31, 2013
Cross-currency swap	$	(1,036	)		Other long-term liabilities
Warrants	$	107			Other long-term assets

Schedule of Gain (Loss) Recognized on Derivative Instruments

	Three Months Ended June 30,					Six Months Ended June 30,
(U.S. Dollars, in thousands)	2014			2013		2014		2013
Cross-currency swap and warrants unrealized gain (loss) recorded in other comprehensive income (loss), net of taxes	$	(31	)	$	222	$	72	$	(96	)