Retirement Plans (Tables)

12 Months Ended

Dec. 31, 2015

Compensation And Retirement Disclosure [Abstract]

Change in Benefit Obligation, Fair Value of Plan Assets, and Funded Status of Pension Plans and Postretirement Medical Plan

The following table summarizes the benefit obligations, the fair value of plan assets, and the funded status of our pension and postretirement medical plans:

	Funded						Unfunded						Postretirement
	Pension Plans						Pension Plan						Medical Plan
	2015			2014			2015			2014			2015			2014
	(In millions)
Change in benefit obligation
Balance at January 1	$	2,450		$	1,957		$	278		$	253		$	94		$	97
Service cost		51			45			16			12			4			4
Interest cost		93			91			9			9			3			3
Actuarial (gain) loss (a)		(156	)		470			(2	)		61			5			(4	)
Benefit payments (b)		(85	)		(77	)		(42	)		(57	)		(8	)		(6	)
Plan curtailments		(4	)		(3	)		—			—			—			—
Special termination benefits		1			2			—			—			—			—
Foreign currency exchange rate changes		(29	)		(35	)		—			—			—			—
Balance at December 31		2,321			2,450			259			278			98			94
Change in fair value of plan assets
Balance at January 1	$	2,251		$	2,145		$	—		$	—		$	—		$	—
Actual return on plan assets		28			151			—			—			—			—
Employer contributions		44			68			42			57			8			6
Benefit payments (b)		(85	)		(77	)		(42	)		(57	)		(8	)		(6	)
Foreign currency exchange rate changes		(32	)		(36	)		—			—			—			—
Balance at December 31		2,206			2,251			—			—			—			—
Funded status (plan assets greater (less) than benefit obligations) at December 31	$	(115	)	$	(199	)	$	(259	)	$	(278	)	$	(98	)	$	(94	)
Unrecognized net actuarial (gains) losses		775			859			105			135			—			(5	)

(a) The change in discount rate and mortality assumptions in 2014 resulted in total actuarial losses of approximately $330 million and $125 million, respectively.

(b) Benefit payments include lump-sum settlement payments of $41 million in 2015 and $55 million in 2014.

Pension Plans and Postretirement Medical Plan Amounts Recognized in Consolidated Balance Sheet

  Amounts recognized in the Consolidated Balance Sheet at December 31 consisted of the following:

	Funded						Unfunded						Postretirement
	Pension Plans						Pension Plan						Medical Plan
	2015			2014			2015			2014			2015			2014
	(In millions)
Pension asset / (accrued benefit liability)	$	(115	)	$	(199	)	$	(259	)	$	(278	)	$	(98	)	$	(94	)
Accumulated other comprehensive loss, pre-tax (a)		775			859			105			135			—			(5	)

(a) The after‑tax deficit reflected in Accumulated other comprehensive income (loss) was $563 million at December 31, 2015 (2014: $652 million).

Components of Net Periodic Benefit Cost for Funded and Unfunded Pension Plans and Postretirement Medical Plan

The net periodic benefit cost for funded and unfunded pension plans, and the postretirement medical plan, is as follows:

	Pension Plans									Postretirement Medical Plan
	2015			2014			2013			2015		2014		2013
	(In millions)
Service cost	$	67		$	57		$	73		$	4	$	4	$	4
Interest cost		102			100			89			3		3		3
Expected return on plan assets		(168	)		(161	)		(141	)		—		—		—
Amortization of unrecognized net actuarial losses		75			32			61			—		—		1
Settlement loss		17			24			—			—		—		—
Curtailment loss		—			—			1			—		—		—
Special termination benefit recognized		1			1			5			—		—		—
Net periodic benefit cost	$	94		$	53		$	88		$	7	$	7	$	8

Actuarial Assumptions Used For Pension Plans & Postretirement Medical Plan

The weighted average actuarial assumptions used for funded and unfunded pension plans were as follows:

	2015			2014			2013
Weighted average assumptions used to determine benefit obligations at December 31
Discount rate		4.1	%		3.8	%		4.6	%
Rate of compensation increase		4.5	%		5.0	%		4.4	%
Weighted average assumptions used to determine net periodic benefit cost for the years ended December 31
Discount rate		3.8	%		4.6	%		4.0	%
Expected return on plan assets		7.5	%		7.5	%		7.5	%
Rate of compensation increase		5.0	%		4.4	%		4.3	%

The actuarial assumptions used for postretirement medical plan, as follows:

	2015			2014			2013
Assumptions used to determine benefit obligations at December 31
Discount rate		3.5	%		3.1	%		3.6	%
Initial health care trend rate		6.7	%		6.8	%		7.1	%
Ultimate trend rate		4.5	%		4.5	%		4.6	%
Year in which ultimate trend rate is reached		2038			2029			2027

Fair Value of Financial Assets of Funded Pension Plans

The following tables provide the fair value of the financial assets of the funded pension plans as of December 31, 2015 and 2014 in accordance with the fair value measurement hierarchy described in Note 1, Nature of Operations, Basis of Presentation and Summary of Accounting Policies included herewith.

	Level 1		Level 2		Level 3		Total
	(In millions)
December 31, 2015
Cash and short-term investment funds	$	—	$	34	$	—	$	34
Equities:
U.S. equities (domestic)		556		—		—		556
International equities (non-U.S.)		159		266		—		425
Global equities (domestic and non-U.S.)		2		217		—		219
Fixed income:
Treasury and government issued (a)		—		213		—		213
Government related (b)		—		6		1		7
Mortgage-backed securities (c)		—		174		2		176
Corporate		—		157		—		157
Other:
Hedge funds		—		—		216		216
Private equity funds		—		—		122		122
Real estate funds		12		—		52		64
Diversified commodities funds		—		17		—		17
	$	729	$	1,084	$	393	$	2,206
December 31, 2014
Cash and short-term investment funds	$	6	$	47	$	—	$	53
Equities:
U.S. equities (domestic)		719		—		—		719
International equities (non-U.S.)		72		177		—		249
Global equities (domestic and non-U.S.)		10		218		—		228
Fixed income:
Treasury and government issued (a)		—		222		—		222
Government related (b)		—		7		1		8
Mortgage-backed securities (c)		—		147		1		148
Corporate		3		137		—		140
Other:
Hedge funds		—		—		302		302
Private equity funds		—		—		105		105
Real estate funds		12		—		48		60
Diversified commodities funds		—		17		—		17
	$	822	$	972	$	457	$	2,251

(a) Includes securities issued and guaranteed by U.S. and non‑U.S. governments.

(b) Primarily consists of securities issued by governmental agencies and municipalities.

(c) Comprised of U.S. residential and commercial mortgage-backed securities.

Changes in Financial Assets that are Measured at Fair Value Based on Level 3 Inputs that are held by Institutional Funds

The following tables provide changes in financial assets that are measured at fair value based on Level 3 inputs that are held by institutional funds classified as:

							Private			Real
	Fixed			Hedge			Equity			Estate
	Income			Funds			Funds			Funds			Total
	(In millions)
Balance at January 1, 2014	$	3		$	291		$	89		$	47		$	430
Actual return on plan assets		—			9			15			—			24
Purchases, sales or other settlements		(1	)		2			1			1			3
Net transfers in (out) of Level 3		—			—			—			—			—
Balance at December 31, 2014		2			302			105			48			457
Actual return on plan assets		—			(5	)		18			9			22
Purchases, sales or other settlements		1			(81	)		(1	)		(5	)		(86	)
Net transfers in (out) of Level 3		—			—			—			—			—
Balance at December 31, 2015	$	3		$	216		$	122		$	52		$	393

Estimated Future Benefit Payments for Funded and Unfunded Pension Plans and Postretirement Medical Plan

Estimated future benefit payments by the funded and unfunded pension plans, and the postretirement medical plan, which reflect expected future service, are as follows (in millions):

2016	$	111
2017		117
2018		120
2019		129
2020		134
Years 2021 to 2025		711