Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0001389050 (http://www.sec.gov/CIK)

Payables and Accruals [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Payables and Accruals [Abstract]
Summary of accrued liabilities	Accrued liabilities consisted of the following (in thousands):   December 31,   2016   2015 Accrued salaries and other benefits $ 25,427   $ 27,066 Accrued income and other taxes 13,742   15,006 Accrued interest 12,392   12,675 Interest rate swaps fair value 3,226   4,608 Accrued other liabilities 14,852   20,698 Accrued liabilities $ 69,639   $ 80,053