Compensation and Benefit Plans (Details 2) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Target asset allocations
Permissible range of asset class portfolio weights	within plus or minus 3%
Percentage of premium based on assumed average equity risk premium over cash (as a percent)	6.00%
Percentage of premium included in estimated rate of return of public equity (as a percent)	3.00%
Stock Options
Outstanding, at the beginning of period (in options)	19,142,209
Granted (in options)	3,467,254
Expired (in options)	(200,075)
Forfeited (in options)	(387,284)
Exercised (in options)	(2,307,890)
Outstanding, at the end of period (in options)	19,714,214
Vested and expected to vest, at the end of period (in options)	19,242,454
Exercisable, at the end of period (in options)	11,238,882
Weighted-Average Exercise Price
Outstanding, at the beginning of period (in dollars per option)	$ 33.28
Granted (in dollars per option)	$ 38.02
Expired (in dollars per option)	$ 48.85
Forfeited (in dollars per option)	$ 33.16
Exercised (in dollars per option)	$ 25.59
Outstanding, at the end of period (in dollars per option)	$ 34.86
Vested and expected to vest, at the end of period (in dollars per option)	$ 34.88
Exercisable, at the end of period (in dollars per option)	$ 35.52
Weighted-Average Remaining Contractual Term (Years)
Outstanding, at the end of period (in years)	5.94
Vested and expected to vest, at the end of period (in years)	5.89
Exercisable, at the end of period (in years)	4.36
Aggregate Intrinsic Value
Vested and expected to vest, at the end of period	$ 156
Exercisable, at the end of period	93
Performance Shares
Weighted-Average Fair Value
Total unrecognized compensation cost	4
Weighted-average period, recognition of unrecognized compensation cost (in years)	2
Performance shares classified as equity awards
Performance Shares
Nonvested, at the beginning of the period (in shares)	415,028
Granted (in shares)	156,765
Forfeited (in shares)	(120,244)	[1]
Nonvested, at the end of the period (in shares)	451,549
Weighted-Average Fair Value
Nonvested, at the beginning of the period (in dollars per share)	$ 30.99
Granted (in dollars per share)	$ 29.97
Forfeited (in dollars per share)	$ 42.60	[1]
Nonvested, at the end of the period (in dollars per share)	$ 27.92
Performance shares classified as liability awards
Performance Shares
Nonvested, at the beginning of the period (in shares)	415,028
Granted (in shares)	156,765
Forfeited (in shares)	(120,244)	[1]
Nonvested, at the end of the period (in shares)	451,549
Weighted-Average Fair Value
Nonvested, at the beginning of the period (in dollars per share)	$ 34.74
Nonvested, at the end of the period (in dollars per share)	$ 29.61
Restricted Stock Units
Performance Shares
Nonvested, at the beginning of the period (in shares)	644,796
Granted (in shares)	256,208
Forfeited (in shares)	(27,813)
Paid out (in shares)	(135,556)
Nonvested, at the end of the period (in shares)	737,635		644,796
Weighted-Average Fair Value
Nonvested, at the beginning of the period (in dollars per share)	$ 32.18
Granted (in dollars per share)	$ 38.01		$ 32.12		$ 25.21
Forfeited (in dollars per share)	$ 32.19
Paid out (in dollars per share)	$ 47.42
Nonvested, at the end of the period (in dollars per share)	$ 32.20		$ 32.18
Total unrecognized compensation cost	8
Compensation cost to be recognized in 2012	3
Compensation cost to be recognized in 2013	5
Stock Options
Weighted-Average Fair Value
Total unrecognized compensation cost	20
Weighted-average period, recognition of unrecognized compensation cost (in years)	2
Pension Plans
Target asset allocations
U.S. Equities investment (as a percent)	30.00%
Non U.S. Equities investment (as a percent)	16.00%
Fixed income investment (as a percent)	35.00%
Opportunistic and/or alternative investments (as a percent)	15.00%
Other investments (as a percent)	4.00%
Master Trust investments at fair value
Total	3,192		3,290
Receivables and payables, net	(39)		(55)
Combined net plan assets available for benefits	3,153		3,235		2,857
Percentage of publicly traded equity investments located in United States (as a percent)	69.00%		69.00%
Pension Plans | Corporate stocks
Master Trust investments at fair value
Total	642	[2]	786	[2]
Pension Plans | Corporate stocks | Russell Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	60.00%		63.00%
Pension Plans | Corporate stocks | MSCI Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	40.00%		37.00%
Pension Plans | Collateralized mortgage obligations and other asset backed securities
Master Trust investments at fair value
Total	53		65
Fair value of assets below investment grade	10		17
Pension Plans | Common/collective funds
Master Trust investments at fair value
Total	582	[3]	600	[3]
Pension Plans | Equity index fund | S&P 500 Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	29.00%		29.00%
Pension Plans | Equity index fund | EAFE Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	10.00%		11.00%
Pension Plans | Undervalued securities | Russell Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	27.00%		28.00%
Pension Plans | Non-index fund
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	23.00%		23.00%
Pension Plans | Global asset allocation fund
Master Trust investments at fair value
Actual plan asset allocation (as a percent)	8.00%		8.00%
Pension Plans | Corporate bonds
Master Trust investments at fair value
Total	497	[4]	555	[4]
Pension Plans | Partnerships joint ventures
Master Trust investments at fair value
Total	588	[5]	500	[5]
Pension Plans | U.S. government and agency securities
Master Trust investments at fair value
Total	455	[6]	400	[6]
Pension Plans | Registered investment companies
Master Trust investments at fair value
Total	108	[7]	176	[7]
Pension Plans | Other investment entities
Master Trust investments at fair value
Total	247	[8]	236	[8]
Pension Plans | Interest-bearing cash
Master Trust investments at fair value
Total	5		5
Pension Plans | Others
Master Trust investments at fair value
Total	68		32
Pension Plans | Level 1
Master Trust investments at fair value
Total	829		961
Pension Plans | Level 1 | Corporate stocks
Master Trust investments at fair value
Total	642	[2]	786	[2]
Pension Plans | Level 1 | U.S. government and agency securities
Master Trust investments at fair value
Total	104	[6]	84	[6]
Pension Plans | Level 1 | Registered investment companies
Master Trust investments at fair value
Total	79	[7]	84	[7]
Pension Plans | Level 1 | Interest-bearing cash
Master Trust investments at fair value
Total	5		5
Pension Plans | Level 1 | Others
Master Trust investments at fair value
Total	(1)		2
Pension Plans | Level 2
Master Trust investments at fair value
Total	1,915		1,984
Pension Plans | Level 2 | Common/collective funds
Master Trust investments at fair value
Total	582	[3]	600	[3]
Pension Plans | Level 2 | Corporate bonds
Master Trust investments at fair value
Total	497	[4]	555	[4]
Pension Plans | Level 2 | Partnerships joint ventures
Master Trust investments at fair value
Total	140	[5]	155	[5]
Pension Plans | Level 2 | U.S. government and agency securities
Master Trust investments at fair value
Total	351	[6]	316	[6]
Pension Plans | Level 2 | Registered investment companies
Master Trust investments at fair value
Total	29	[7]	92	[7]
Pension Plans | Level 2 | Other investment entities
Master Trust investments at fair value
Total	247	[8]	236	[8]
Pension Plans | Level 2 | Others
Master Trust investments at fair value
Total	69		30
Pension Plans | Level 3
Master Trust investments at fair value
Total	448		345
Combined net plan assets available for benefits	448		345		240
Pension Plans | Level 3 | Partnerships joint ventures
Master Trust investments at fair value
Total	448	[5]	345	[5]
Pension Plans | Level 3 | Asset backed securities including distressed mortgages
Master Trust investments at fair value
Actual plan asset allocation (as a percent)	55.00%		60.00%
Postretirement Benefits Other Than Pensions
Target asset allocations
U.S. Equities investment (as a percent)	41.00%
Non U.S. Equities investment (as a percent)	17.00%
Fixed income investment (as a percent)	34.00%
Opportunistic and/or alternative investments (as a percent)	7.00%
Other investments (as a percent)	1.00%
Master Trust investments at fair value
Total	1,593		1,618
Receivables and payables, net	(23)		(12)
Combined net plan assets available for benefits	1,570		1,606		1,459
Percentage of publicly traded equity investments located in United States (as a percent)	69.00%		67.00%
Postretirement Benefits Other Than Pensions | Corporate stocks
Master Trust investments at fair value
Total	319	[9]	344	[9]
Postretirement Benefits Other Than Pensions | Corporate stocks | Russell Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	53.00%		54.00%
Postretirement Benefits Other Than Pensions | Corporate stocks | MSCI All Country World Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	47.00%		46.00%
Postretirement Benefits Other Than Pensions | Corporate notes and bonds
Master Trust investments at fair value
Total	177	[10]	184	[10]
Postretirement Benefits Other Than Pensions | Collateralized mortgage obligations and other asset backed securities
Master Trust investments at fair value
Receivables and payables, net	14		15
Postretirement Benefits Other Than Pensions | Common/collective funds
Master Trust investments at fair value
Total	642	[11]	657	[11]
Postretirement Benefits Other Than Pensions | Equity index fund | EAFE Index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	21.00%		23.00%
Postretirement Benefits Other Than Pensions | Undervalued securities
Target asset allocations
U.S. Equities investment (as a percent)	6.00%		6.00%
Postretirement Benefits Other Than Pensions | Private bond
Target asset allocations
U.S. Equities investment (as a percent)	6.00%		7.00%
Postretirement Benefits Other Than Pensions | Common or collective equity funds | Russell 1000 index
Master Trust investments at fair value
Percentage of performance to benchmark (as a percent)	63.00%		61.00%
Postretirement Benefits Other Than Pensions | Partnerships joint ventures
Master Trust investments at fair value
Total	146	[12]	108	[12]
Postretirement Benefits Other Than Pensions | U.S. government and agency securities
Master Trust investments at fair value
Total	142	[13]	88	[13]
Postretirement Benefits Other Than Pensions | Registered investment companies
Master Trust investments at fair value
Total	80	[14]	145	[14]
Postretirement Benefits Other Than Pensions | Interest-bearing cash
Master Trust investments at fair value
Total	12		12
Postretirement Benefits Other Than Pensions | Others
Master Trust investments at fair value
Total	75	[15]	80	[15]
Postretirement Benefits Other Than Pensions | Municipal securities
Master Trust investments at fair value
Total	60		64
Postretirement Benefits Other Than Pensions | Level 1
Master Trust investments at fair value
Total	515		554
Postretirement Benefits Other Than Pensions | Level 1 | Corporate stocks
Master Trust investments at fair value
Total	319	[9]	344	[9]
Postretirement Benefits Other Than Pensions | Level 1 | U.S. government and agency securities
Master Trust investments at fair value
Total	100	[13]	50	[13]
Postretirement Benefits Other Than Pensions | Level 1 | Registered investment companies
Master Trust investments at fair value
Total	80	[14]	144	[14]
Postretirement Benefits Other Than Pensions | Level 1 | Interest-bearing cash
Master Trust investments at fair value
Total	12		12
Postretirement Benefits Other Than Pensions | Level 1 | Others
Master Trust investments at fair value
Total	4	[15]	4	[15]
Postretirement Benefits Other Than Pensions | Level 2
Master Trust investments at fair value
Total	948		972
Postretirement Benefits Other Than Pensions | Level 2 | Corporate notes and bonds
Master Trust investments at fair value
Total	177	[10]	184	[10]
Postretirement Benefits Other Than Pensions | Level 2 | Common/collective funds
Master Trust investments at fair value
Total	642	[11]	657	[11]
Postretirement Benefits Other Than Pensions | Level 2 | Partnerships joint ventures
Master Trust investments at fair value
Total	16	[12]	16	[12]
Postretirement Benefits Other Than Pensions | Level 2 | U.S. government and agency securities
Master Trust investments at fair value
Total	42	[13]	38	[13]
Postretirement Benefits Other Than Pensions | Level 2 | Registered investment companies
Master Trust investments at fair value
Total	0	[14]	1	[14]
Postretirement Benefits Other Than Pensions | Level 2 | Others
Master Trust investments at fair value
Total	71	[15]	76	[15]
Postretirement Benefits Other Than Pensions | Level 3
Master Trust investments at fair value
Total	130		92
Combined net plan assets available for benefits	130		92		49
Postretirement Benefits Other Than Pensions | Level 3 | Partnerships joint ventures
Master Trust investments at fair value
Total	$ 130	[12]	$ 92	[12]
Postretirement Benefits Other Than Pensions | Level 3 | Asset backed securities including distressed mortgages
Master Trust investments at fair value
Actual plan asset allocation (as a percent)	81.00%		84.00%

[1] Includes performance shares that expired with zero value as performance targets were not met.

[2] Corporate stocks are diversified. For 2011 and 2010, respectively, performance is primarily benchmarked against the Russell Indexes (60% and 63%) and Morgan Stanley Capital International (MSCI) index (40% and 37%).

[3] At December 31, 2011 and 2010, respectively, the common/collective assets were invested in equity index funds that seek to track performance of the Standard and Poor's (S&P 500) Index (29% and 29%), Russell 200 and Russell 1000 indexes (27% and 28%) and the MSCI Europe, Australasia and Far East (EAFE) Index (10% and 11%). A non-index U.S. equity fund representing 23% of this category for both 2011 and 2010 is actively managed. Another fund representing 8% of this category for both 2011 and 2010 is a global asset allocation fund.

[4] Corporate bonds are diversified. At December 31, 2011 and 2010, respectively, this category includes $53 million and $65 million for collateralized mortgage obligations and other asset backed securities of which $10 million and $17 million are below investment grade.

[5] Partnerships/joint venture Level 2 investments consist primarily of a partnership which invests in publicly traded fixed income securities, primarily from the banking and finance industry and U.S. government agencies. At December 31, 2011 and 2010, respectively, approximately 55% and 60% of the Level 3 partnerships are invested in (1) asset backed securities, including distressed mortgages and (2) commercial and residential loans and debt and equity of banks. The remaining Level 3 partnerships are invested in small private equity and venture capital funds. Investment strategies for these funds include branded consumer products, early stage technology, California geographic focus, and diversified US and non-US fund-of-funds.

[6] Level 1 U.S. government and agency securities are U.S. treasury bonds and notes. Level 2 primarily relates to the Federal National Mortgage Association and the Federal Home Loan Mortgage Corporation.

[7] Level 1 of registered investment companies consisted of a global equity mutual fund which seeks to outperform the MSCI World Total Return Index. Level 2 primarily consisted of short-term, emerging market, high yield bond funds and government inflation-indexed bonds.

[8] Other investment entities were primarily invested in (1) emerging market equity securities, (2) a hedge fund that invests through liquid instruments in a global diversified portfolio of equity, fixed income, interest rate, foreign currency and commodities markets, and (3) domestic mortgage backed securities.

[9] Corporate stock performance is primarily benchmarked against the Russell Indexes (53% and 54%) and the MSCI All Country World (ACWI) index (47% and 46%) for 2011 and 2010, respectively.

[10] Corporate notes and bonds are diversified and include approximately $14 million and $15 million for commercial collateralized mortgage obligations and other asset backed securities at December 31, 2011 and 2010, respectively.

[11] At December 31, 2011 and 2010, respectively, 63% and 61% of the common/collective assets are invested in a large cap index fund which seeks to track performance of the Russell 1000 index. 21% and 23% of the assets in this category are in index funds which seek to track performance in the MSCI Europe, Australasia and Far East (EAFE) Index. 6% and 7% of this category are invested in a privately managed bond fund and 6% and 6% in a fund which invests in equity securities the fund manager believes are undervalued.

[12] At December 31, 2011 and 2010, respectively, 81% and 84% of the Level 3 partnerships category is invested in (1) asset backed securities including distressed mortgages, (2) distressed companies and (3) commercial and residential loans and debt and equity of banks.

[13] Level 1 U.S. government and agency securities are U.S. treasury bonds and notes. Level 2 primarily relates to the Federal Home Loan Mortgage Corporation and the Federal National Mortgage Association.

[14] Level 1 registered investment companies consist of an investment grade corporate bond mutual fund and a money market fund.

[15] Other includes $60 million and $64 million of municipal securities at December 31, 2011 and 2010, respectively.