Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands	Sep. 30, 2011		Dec. 31, 2010
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustments	$ 42,245	[1]	$ 30,931	[1]
Joint venture cash flow hedges	(1,966)		(1,468)
Unrecognized components of employee benefit plans, net of tax	(91,372)		(97,821)
Total	$ (51,093)		$ (68,358)

[1] During the nine months ended September 30, 2011, the increase in net foreign currency translation adjustments was due to the strengthening of the New Zealand dollar against the U.S. dollar.