Employee Benefit Plans (Details 12) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 7,879	$ 7,108	$ 6,310
United States Pension Plans of US Entity, Defined Benefit [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,279	1,964
United States Pension Plans of US Entity, Defined Benefit [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	336	287
United States Pension Plans of US Entity, Defined Benefit [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	769	218
United States Pension Plans of US Entity, Defined Benefit [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,313	1,194
United States Pension Plans of US Entity, Defined Benefit [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	258	184
United States Pension Plans of US Entity, Defined Benefit [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	497	475
United States Pension Plans of US Entity, Defined Benefit [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,452	4,322
United States Pension Plans of US Entity, Defined Benefit [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,267	1,393
United States Pension Plans of US Entity, Defined Benefit [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	362	287
United States Pension Plans of US Entity, Defined Benefit [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,629	1,680
United States Pension Plans of US Entity, Defined Benefit [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	564	600
United States Pension Plans of US Entity, Defined Benefit [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	214	405
United States Pension Plans of US Entity, Defined Benefit [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12	2
United States Pension Plans of US Entity, Defined Benefit [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	44
United States Pension Plans of US Entity, Defined Benefit [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		47
United States Pension Plans of US Entity, Defined Benefit [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		8
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,610	2,480
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,153	1,007
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,154	1,008
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,092	1,149
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	362	287
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,454	1,436
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	4
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	30
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,650	3,848
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,260	1,932
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	335	286
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	761	213
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	160	187
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	258	184
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	490	473
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,264	3,275
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	38	38
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	38	38
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	117	69
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	214	401
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	10
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		47
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		8
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	619	780
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	19	32	49	68
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	5	4	5
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	2	2	69
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	34	39
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	137	206	240	241
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	137	206
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	447	531	471	373
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	4	0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
United States Pension Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Foreign Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	224	185	178
Foreign Pension Plans, Defined Benefit [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	120	96
Foreign Pension Plans, Defined Benefit [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	43
Foreign Pension Plans, Defined Benefit [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	24	19
Foreign Pension Plans, Defined Benefit [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	6
Foreign Pension Plans, Defined Benefit [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13	13
Foreign Pension Plans, Defined Benefit [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	8
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	24	19
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	24	19
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 1 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	180	145
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	120	96
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54	43
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6	6
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 2 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20	21
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13	13	11	0
Foreign Pension Plans, Defined Benefit [Member] | Level 3 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	7	8	8	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,320	1,240	1,185
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	169	143
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	26	29
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	51	13
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	178	161
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	71	60
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	58	89
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	553	495
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	250	242
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	83	55
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	333	297
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	432	441
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	508	461
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	175	160
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	175	160
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	249	240
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	83	55
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	332	295
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	6
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 1 [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	804	768
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	165	139
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	26	29
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	51	13
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	1
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	70	59
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	55	84
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	370	325
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	2
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	2
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	432	435
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		4
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 2 [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	11
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Corporate fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	4	4	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | US Government Agencies Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | US Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | State and political subdivision securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1	1	1	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Other Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	5	6	9
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Fixed maturity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	8	10
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Common Stock-domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Money Market Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	1	0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Other receivables [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
United States Postretirement Benefit Plans of US Entity, Defined Benefit [Member] | Level 3 [Member] | Securities receivable [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Foreign Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	13	15
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	13
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 1 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	13
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15	13
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 2 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member] | Foreign government debt securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member] | Common Stock-foreign [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member] | Other invested assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member] | Short-term Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member] | Derivatives [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Postretirement Benefit Plans, Defined Benefit [Member] | Level 3 [Member] | Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0