Supplemental Financial Information (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Supplemental Financial Information
Net earnings allocated to common shares	$ 473,000,000	$ 1,711,000,000	$ 1,013,000,000	$ 2,943,000,000
Income from resolution of contractual agreement				40,000,000
Component of long-term investment
Payments for settlement of certain government investigations				800,000,000
Long-term Investment Securities	154,268,000		154,268,000		273,595,000
Defined Benefit Plans
Component of long-term investment
Benefit plan contributions by employer			320,000,000	320,000,000
Equity securities
Component of long-term investment
Long-term Investment Securities	126,000,000		126,000,000		213,000,000
Other
Component of long-term investment
Long-term Investment Securities	$ 28,000,000		$ 28,000,000		$ 61,000,000