Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Preferred stock, no par value	$ 0	$ 0	[1]
Preferred stock, authorized	1,000,000	1,000,000	[1]
Preferred stock, issued	0	0	[1]
Common stock, par value	$ 1	$ 1	[1]
Common stock, authorized	1,200,000,000	1,200,000,000	[1]
Common stock, issued	353,700,000	353,400,000	[1]

[1] The December 31, 2012 consolidated balance sheet has been derived from audited financial statements.