Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator for Basic and Diluted Earnings Per Share - [Abstract]
Net Income (Loss)	$ 5,268	$ 706,353	$ (164,480)	$ 1,367,281
Denominator for Basic Earnings Per Share - [Abstract]
Weighted Average Shares	545,504	543,099	545,245	542,675
Potential Dilutive Common Shares -[Abstract]
Stock Options/SARs	1,960	2,759	0	2,597
Restricted Stock/Units and Performance Units/Stock	2,219	2,818	0	2,774
Denominator for Diluted Earnings Per Share - [Abstract]
Adjusted Diluted Weighted Average Shares	549,683	548,676	545,245	548,046
Net Income (Loss) Per Share [Abstract]
Basic	$ 0.01	$ 1.30	$ (0.30)	$ 2.52
Diluted	$ 0.01	$ 1.29	$ (0.30)	$ 2.49
Anti-dilutive Stock Options and SARs excluded from Diluted Earnings Per Share Calculation (shares in thousands)	2,000	6	10,000	100
Restricted Stock and Restricted Stock Units and Performance Units and Performance Stock Excluded from Calculation			5,500