Consolidated Statements of Cash Flows Supplemental Information (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Supplemental Cash Flow Information [Abstract]
Stock contribution to pension plans, value			$ 9,815
Convertible note repurchases, shares	0	0
Convertible note repurchases, value			17,019
Treasury Stock [Member]
Supplemental Cash Flow Information [Abstract]
Stock contribution to pension plans, shares			737,463
Stock contribution to pension plans, value			$ 16,370
Convertible note repurchases, shares			1,154,265