Postemployment benefit plans (Tables)

12 Months Ended

Dec. 31, 2016

Compensation and Retirement Disclosure [Abstract]

Schedule of changes in projected benefit obligations

	U.S. Pension Benefits						Non-U.S.  Pension Benefits						Other Postretirement  Benefits
(Millions of dollars)	2016			2015			2016			2015			2016			2015
Change in benefit obligation:
Benefit obligation, beginning of year	$	15,792		$	16,249		$	4,355		$	4,801		$	4,313		$	4,938
Service cost	119			181			92			110			82			101
Interest cost	517			608			117			146			131			181
Plan amendments	—			—			(5		)	—			(188		)	3
Actuarial losses (gains)	767			(384		)	512			(152		)	60			(625		)
Foreign currency exchange rates	—			—			(369		)	(307		)	14			(43		)
Participant contributions	—			—			7			8			57			52
Benefits paid - gross	(970		)	(890		)	(238		)	(191		)	(388		)	(345		)
Less: federal subsidy on benefits paid	—			—			—			—			11			11
Curtailments, settlements and termination benefits	(7		)	28			1			(60		)	(4		)	40
Benefit obligation, end of year	$	16,218		$	15,792		$	4,472		$	4,355		$	4,088		$	4,313
Accumulated benefit obligation, end of year	$	16,034		$	15,550		$	4,163		$	4,024
Weighted-average assumptions used todetermine benefit obligation:
Discount rate	4.0		%	4.2		%	2.5		%	3.2		%	4.0		%	4.1		%
Rate of compensation increase	4.0		%	4.0		%	4.0		%	3.8		%	4.0		%	4.0		%

Schedule of assumptions used to determine benefit obligation

	U.S. Pension Benefits						Non-U.S.  Pension Benefits						Other Postretirement  Benefits
(Millions of dollars)	2016			2015			2016			2015			2016			2015
Change in benefit obligation:
Benefit obligation, beginning of year	$	15,792		$	16,249		$	4,355		$	4,801		$	4,313		$	4,938
Service cost	119			181			92			110			82			101
Interest cost	517			608			117			146			131			181
Plan amendments	—			—			(5		)	—			(188		)	3
Actuarial losses (gains)	767			(384		)	512			(152		)	60			(625		)
Foreign currency exchange rates	—			—			(369		)	(307		)	14			(43		)
Participant contributions	—			—			7			8			57			52
Benefits paid - gross	(970		)	(890		)	(238		)	(191		)	(388		)	(345		)
Less: federal subsidy on benefits paid	—			—			—			—			11			11
Curtailments, settlements and termination benefits	(7		)	28			1			(60		)	(4		)	40
Benefit obligation, end of year	$	16,218		$	15,792		$	4,472		$	4,355		$	4,088		$	4,313
Accumulated benefit obligation, end of year	$	16,034		$	15,550		$	4,163		$	4,024
Weighted-average assumptions used todetermine benefit obligation:
Discount rate	4.0		%	4.2		%	2.5		%	3.2		%	4.0		%	4.1		%
Rate of compensation increase	4.0		%	4.0		%	4.0		%	3.8		%	4.0		%	4.0		%

Change in plan assets

	U.S. Pension Benefits						Non-U.S.  Pension Benefits						Other Postretirement  Benefits
(Millions of dollars)	2016			2015			2016			2015			2016			2015
Change in plan assets:
Fair value of plan assets, beginning of year	$	11,440		$	12,530		$	3,890		$	4,100		$	650		$	776
Actual return on plan assets	860			(225		)	503			107			55			3
Foreign currency exchange rates	—			—			(392		)	(234		)	—			—
Company contributions	36			30			117			156			176			164
Participant contributions	—			—			7			8			57			52
Benefits paid	(970		)	(890		)	(238		)	(191		)	(388		)	(345		)
Settlements and termination benefits	(12		)	(5		)	—			(56		)	—			—
Fair value of plan assets, end of year	$	11,354		$	11,440		$	3,887		$	3,890		$	550		$	650

Fair value of pension and other postretirement benefit plan assets, by category

The fair value of the pension and other postretirement benefit plan assets by category is summarized below:

	December 31, 2016
(Millions of dollars)	Level 1		Level 2		Level 3		Measured at NAV		Total Assets at Fair Value
U.S. Pension
Equity securities:
U.S. equities	$	2,816	$	—	$	5	$	174	$	2,995
Non-U.S. equities	1,653		5		—		—		1,658
Fixed income securities:
U.S. corporate bonds	—		4,273		31		85		4,389
Non-U.S. corporate bonds	—		710		—		—		710
U.S. government bonds	—		647		—		—		647
U.S. governmental agency mortgage-backed securities	—		491		—		—		491
Non-U.S. government bonds	—		90		—		—		90
Real estate	—		—		10		—		10
Cash, short-term instruments and other	93		74		11		186		364
Total U.S. pension assets	$	4,562	$	6,290	$	57	$	445	$	11,354

	December 31, 2015
(Millions of dollars)	Level 1		Level 2		Level 3		Measured at NAV		Total Assets at Fair Value
U.S. Pension
Equity securities:
U.S. equities	$	2,976	$	—	$	4	$	168	$	3,148
Non-U.S. equities	2,044		5		1		—		2,050
Fixed income securities:
U.S. corporate bonds	—		3,872		42		132		4,046
Non-U.S. corporate bonds	—		575		—		—		575
U.S. government bonds	—		526		—		—		526
U.S. governmental agency mortgage-backed securities	—		627		—		—		627
Non-U.S. government bonds	—		65		—		—		65
Real estate	—		—		9		—		9
Cash, short-term instruments and other	157		28		3		206		394
Total U.S. pension assets	$	5,177	$	5,698	$	59	$	506	$	11,440

We have revised previously reported Level 2, Level 3 and Measured at NAV for U.S. Pension. Level 2 assets decreased $141 million, Level 3 assets increased $9 million and Measured at NAV increased $132 million for the U.S. Pension in 2015. The revision did not impact total assets. Management has concluded that the impact was not material to any period presented.

	December 31, 2016
(Millions of dollars)	Level 1		Level 2		Level 3		Measured at NAV		Total Assets at Fair Value
Non-U.S. Pension
Equity securities:
U.S. equities	$	405	$	—	$	—	$	108	$	513
Non-U.S. equities	639		38		—		119		796
Global equities 1	122		34		—		—		156
Fixed income securities:
U.S. corporate bonds	—		151		1		—		152
Non-U.S. corporate bonds	—		345		1		10		356
U.S. government bonds	—		44		—		—		44
Non-U.S. government bonds	—		1,172		—		—		1,172
Global fixed income 1	—		221		—		199		420
Real estate	—		179		—		—		179
Cash, short-term instruments and other 2	53		46		—		—		99
Total non-U.S. pension assets	$	1,219	$	2,230	$	2	$	436	$	3,887

	December 31, 2015
(Millions of dollars)	Level 1		Level 2		Level 3		Measured at NAV		Total Assets at Fair Value
Non-U.S. Pension
Equity securities:
U.S. equities	$	426	$	—	$	—	$	118	$	544
Non-U.S. equities	680		29		2		123		834
Global equities 1	155		49		—		—		204
Fixed income securities:
U.S. corporate bonds	—		135		3		—		138
Non-U.S. corporate bonds	—		389		2		11		402
U.S. government bonds	—		64		—		—		64
Non-U.S. government bonds	—		1,083		—		—		1,083
Global fixed income 1	—		166		—		175		341
Real estate	—		172		—		—		172
Cash, short-term instruments and other 2	61		47		—		—		108
Total non-U.S. pension assets	$	1,322	$	2,134	$	7	$	427	$	3,890

¹  Includes funds that invest in both U.S. and non-U.S. securities.

²  Includes funds that invest in multiple asset classes, hedge funds and other.

	December 31, 2016
(Millions of dollars)	Level 1		Level 2		Level 3		Measured at NAV		Total Assets at Fair Value
Other Postretirement Benefits
Equity securities:
U.S. equities	$	276	$	1	$	—	$	—	$	277
Non-U.S. equities	110		—		—		—		110
Fixed income securities:
U.S. corporate bonds	—		69		—		1		70
Non-U.S. corporate bonds	—		17		—		—		17
U.S. government bonds	—		16		—		—		16
U.S. governmental agency mortgage-backed securities	—		31		—		—		31
Non-U.S. government bonds	—		4		—		—		4
Cash, short-term instruments and other	5		1		—		19		25
Total other postretirement benefit assets	$	391	$	139	$	—	$	20	$	550

	December 31, 2015
(Millions of dollars)	Level 1		Level 2		Level 3		Measured at NAV		Total Assets at Fair Value
Other Postretirement Benefits
Equity securities:
U.S. equities	$	296	$	1	$	—	$	—	$	297
Non-U.S. equities	136		—		—		—		136
Fixed income securities:
U.S. corporate bonds	—		83		—		4		87
Non-U.S. corporate bonds	—		18		—		—		18
U.S. government bonds	—		31		—		—		31
U.S. governmental agency mortgage-backed securities	—		45		—		—		45
Non-U.S. government bonds	—		4		—		—		4
Cash, short-term instruments and other	17		15		—		—		32
Total other postretirement benefit assets	$	449	$	197	$	—	$	4	$	650

Roll forward of assets measured at fair value using level 3 inputs

Below are roll-forwards of assets measured at fair value using Level 3 inputs for the years ended December 31, 2016 and 2015.  These instruments were valued using pricing models that, in management’s judgment, reflect the assumptions a market participant would use.

(Millions of dollars)	Equities			Fixed Income			Real Estate			Other
U.S. Pension
Balance at December 31, 2014	$	9		$	29		$	9		$	—
Unrealized gains (losses)	(1		)	(1		)	—			—
Realized gains (losses)	1			—			—			—
Purchases, issuances and settlements, net	(4		)	16			—			2
Transfers in and/or out of Level 3	—			(2		)	—			1
Balance at December 31, 2015	$	5		$	42		$	9		$	3
Unrealized gains (losses)	—			4			1			—
Realized gains (losses)	—			(5		)	—			—
Purchases, issuances and settlements, net	1			(9		)	—			8
Transfers in and/or out of Level 3	(1		)	(1		)	—			—
Balance at December 31, 2016	$	5		$	31		$	10		$	11
Non-U.S. Pension
Balance at December 31, 2014	$	—		$	11		$	39		$	—
Unrealized gains (losses)	—			(1		)	(17		)	—
Realized gains (losses)	—			—			15			—
Purchases, issuances and settlements, net	—			—			(37		)	—
Transfers in and/or out of Level 3	2			(5		)	—			—
Balance at December 31, 2015	$	2		$	5		$	—		$	—
Unrealized gains (losses)	—			—			—			—
Realized gains (losses)	(1		)	—			—			—
Purchases, issuances and settlements, net	(1		)	(1		)	—			—
Transfers in and/or out of Level 3	—			(2		)	—			—
Balance at December 31, 2016	$	—		$	2		$	—		$	—

Defined benefit plan funded status, components of net amount recognized in financial position and accumulated other comprehensive income

The funded status of the plans, reconciled to the amount reported on Statement 3, is as follows:

	U.S. Pension Benefits						Non-U.S.  Pension Benefits						Other Postretirement Benefits
(Millions of dollars)	2016			2015			2016			2015			2016			2015
End of Year
Fair value of plan assets	$	11,354		$	11,440		$	3,887		$	3,890		$	550		$	650
Benefit obligations	16,218			15,792			4,472			4,355			4,088			4,313
Over (under) funded status recognized in financial position	$	(4,864	)	$	(4,352	)	$	(585	)	$	(465	)	$	(3,538	)	$	(3,663	)
Components of net amount recognized in financial position:
Other assets (non-current asset)	$	4		$	6		$	152		$	163		$	—		$	—
Accrued wages, salaries and employee benefits (current liability)	(35		)	(32		)	(20		)	(19		)	(162		)	(161		)
Liability for postemployment benefits (non-current liability)	(4,833		)	(4,326		)	(717		)	(609		)	(3,376		)	(3,502		)
Net liability recognized	$	(4,864	)	$	(4,352	)	$	(585	)	$	(465	)	$	(3,538	)	$	(3,663	)
Amounts recognized in Accumulated other comprehensive income (pre-tax) consist of:
Prior service cost (credit)	$	—		$	1		$	(5	)	$	1		$	(85	)	$	39

Estimated amounts that will be amortized from Accumulated other comprehensive income (loss) into net periodic benefit cost (pre-tax) in the next fiscal year

The estimated amount of prior service cost (credit) that will be amortized from Accumulated other comprehensive income (loss) at December 31, 2016 into net periodic benefit cost (pre-tax) in 2017 are as follows:

(Millions of dollars)	U.S. Pension Benefits		Non-U.S. Pension Benefits			Other Postretirement Benefits
Prior service cost (credit)	$	—	$	(1	)	$	(21	)

Schedule of pension plans with projected benefit obligation in excess of plan assets for all U.S and Non U.S Pension benefits

The following amounts relate to our pension plans with projected benefit obligations in excess of plan assets:

	U.S. Pension Benefits at Year-end				Non-U.S. Pension Benefits at Year-end
(Millions of dollars)	2016		2015		2016		2015
Projected benefit obligation	$	16,163	$	15,734	$	4,098	$	1,818
Accumulated benefit obligation	$	15,979	$	15,493	$	3,835	$	1,657
Fair value of plan assets	$	11,295	$	11,377	$	3,361	$	1,190

Schedule of pension plans with accumulated benefit obligation in excess of plan assets for all U.S and Non U.S Pension benefits

The following amounts relate to our pension plans with accumulated benefit obligations in excess of plan assets:

	U.S. Pension Benefits at Year-end				Non-U.S. Pension Benefits at Year-end
(Millions of dollars)	2016		2015		2016		2015
Projected benefit obligation	$	16,163	$	15,734	$	1,707	$	1,363
Accumulated benefit obligation	$	15,979	$	15,493	$	1,607	$	1,320
Fair value of plan assets	$	11,295	$	11,377	$	1,024	$	793

Information about the expected contributions and benefit payments for the pension and other postretirement benefit plans

Information about expected contributions and benefit payments for pension and other postretirement benefit plans is as follows:

(Millions of dollars)	U.S. Pension Benefits		Non-U.S. Pension Benefits		Other Postretirement Benefits
Employer contributions:
2017 (expected)	$	350	$	100	$	160
Expected benefit payments:
2017	$	1,020	$	190	$	310
2018	980		160		300
2019	990		160		300
2020	990		160		290
2021	990		170		280
2022-2026	4,900		970		1,320
Total	$	9,870	$	1,810	$	2,800

Expected Medicare Part D subsidy receipts

Medicare Part D subsidy amounts expected to be received by the company which will offset other postretirement benefit payments are as follows:

(Millions of dollars)	2017		2018		2019		2020		2021		2022-2026		Total
Other postretirement benefits	$	15	$	15	$	20	$	20	$	20	$	95	$	185

Components of net periodic benefit cost, other changes in plan assets and benefits obligations recognized in other comprehensive income and weighted-average assumptions used to determine net cost

	U.S. Pension Benefits									Non-U.S. Pension Benefits									Other Postretirement Benefits
(Millions of dollars)	2016			2015			2014			2016			2015			2014			2016			2015			2014
Components of net periodic benefit cost:
Service cost	$	119		$	181		$	157		$	92		$	110		$	109		$	82		$	101		$	82
Interest cost	517			608			648			117			146			185			131			181			213
Expected return on plan assets 1	(757		)	(890		)	(943		)	(227		)	(273		)	(271		)	(44		)	(56		)	(58		)
Curtailments and termination benefits 2	6			32			—			1			(1		)	2			(9		)	27			(4		)
Amortization of prior service cost (credit) 3	—			1			17			3			—			—			(59		)	(54		)	(55		)
Actuarial loss (gain) 4	664			732			2,088			262			8			345			59			(561		)	191
Total cost (benefit) included in operating profit	$	549		$	664		$	1,967		$	248		$	(10	)	$	370		$	160		$	(362	)	$	369
Other changes in plan assets and benefit obligations recognized in other comprehensive income (pre-tax):
Current year prior service cost (credit)	$	—		$	—		$	—		$	(3	)	$	(8	)	$	(4	)	$	(184	)	$	16		$	(2	)
Amortization of prior service (cost) credit	—			(1		)	(17		)	(3		)	—			—			59			54			55
Total recognized in other comprehensive income	—			(1		)	(17		)	(6		)	(8		)	(4		)	(125		)	70			53
Total recognized in net periodic cost and other comprehensive income	$	549		$	663		$	1,950		$	242		$	(18	)	$	366		$	35		$	(292	)	$	422
Weighted-average assumptions used to determine net cost:
Discount rate used to measure service cost	4.5		%	3.8		%	4.6		%	2.9		%	3.3		%	4.1		%	4.2		%	3.9		%	4.6		%
Discount rate used to measure interest cost	3.4		%	3.8		%	4.6		%	2.8		%	3.3		%	4.1		%	3.3		%	3.9		%	4.6		%
Expected rate of return on plan assets 5	6.9		%	7.4		%	7.8		%	6.1		%	6.8		%	6.9		%	7.5		%	7.8		%	7.8		%
Rate of compensation increase	4.0		%	4.0		%	4.0		%	3.6		%	4.0		%	4.2		%	4.0		%	4.0		%	4.0		%

¹  Expected return on plan assets developed using the fair value of plan assets.

²  Curtailments and termination benefits were recognized in Other operating (income) expenses in Statement 1.

³  Prior service cost (credit) for both pension and other postretirement benefits are generally amortized using the straight-line method over the average remaining service period of active employees expected to receive benefits from the plan. For pension plans in which all or almost all of the plan's participants are inactive and other postretirement benefit plans in which all or almost all of the plan's participants are fully eligible for benefits under the plan, prior service cost (credit) are amortized using the straight-line method over the remaining life expectancy of those participants.

⁴  Actuarial loss (gain) represent the effects of actual results differing from our assumptions and the effects of changing assumptions. We recognize actuarial loss (gain) immediately through earnings upon the annual remeasurement in the fourth quarter, or on an interim basis as triggering events warrant remeasurement.

⁵  The weighted-average rates for 2017 are 6.7 percent and 5.9 percent for U.S. and non-U.S. pension plans, respectively.

Effects of one-percentage point change in the assumed health care cost trend rates

A one-percentage-point change in assumed health care cost trend rates would have the following effects:

(Millions of dollars)	One-percentage- point increase		One-percentage- point decrease
Effect on 2016 service and interest cost components of other postretirement benefit cost	$	19	$	(15	)
Effect on accumulated postretirement benefit obligation	$	178	$	(150	)

Company costs related to U.S. and non-U.S. defined contribution plans

Total company costs related to U.S. and non-U.S. defined contribution plans were as follows:

(Millions of dollars)	2016		2015		2014
U.S. plans	$	301	$	267	$	301
Non-U.S. plans	68		76		85
	$	369	$	343	$	386

Summary of long-term liability for postemployment benefit plans

	December 31,
(Millions of dollars)	2016		2015
Pensions:
U.S. pensions	$	4,833	$	4,326
Non-U.S. pensions	717		609
Total pensions	5,550		4,935
Postretirement benefits other than pensions	3,376		3,502
Other postemployment benefits	106		104
Defined contribution	325		302
	$	9,357	$	8,843