Earnings (loss) percommon share (Details 13) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Weighted average common shares outstanding - basic	188,831	188,831	188,831	188,811	188,794	188,794	188,794	188,671	188,826	188,763	188,137
Effect of dilutive stock options and performance share awards									0	142	92
Weighted average common shares outstanding - diluted	188,831	188,831	189,107	189,182	188,932	188,797	188,968	188,815	188,826	188,905	188,229
Shares excluded from the calculation of diluted earnings per share									58	0	0