Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jun. 30, 2011	Dec. 31, 2010
Consolidated Balance Sheets
Trade, allowance for doubtful accounts	$ 1,056	$ 1,155
Other, allowance for doubtful accounts	$ 358	$ 2,519
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	127,554,683	126,212,256
Treasury stock, shares	11,311,097	10,903,743