Fair value measurements (Tables)

12 Months Ended

Dec. 31, 2012

Fair Value Disclosures [Abstract]

Schedule of Financial Assets and Liabilities Recorded at Fair Value on Recurring Basis

The fair value of the Company’s financial assets and liabilities on a recurring basis were as follows:

(U.S. Dollars, in thousands)	Balance December 31, 2012		Level 1		Level 2		Level 3
Derivative Financial Instruments (1)
Cash Flow Hedges
Cross currency hedge	$	305	$	—	$	305	$	—

(U.S. Dollars, in thousands)	Balance December 31, 2011		Level 1		Level 2		Level 3
Derivative Financial Instruments (1)
Cash Flow Hedges
Cross currency hedge	$	1,011	$	—	$	1,011	$	—

(1) See Note 10, “Derivative Instruments”.