PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Tables)

12 Months Ended

Dec. 31, 2017

Defined Benefit Plan Disclosure [Line Items]

Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan [Table Text Block]



Change in Projected Benefit Obligations, Plan Assets and Funded Status for all Plans	Defined Benefit Pension Plans						Other Postretirement Benefits
In millions	2017			2016			2017			2016
Change in projected benefit obligations:
Benefit obligation at beginning of year	$	4,025		$	3,993		$	264		$	276
Service cost	38			39			1			1
Interest cost	129			131			8			8
Actuarial changes in assumptions and experience	241			155			(23		)	4
Benefits paid	(281		)	(285		)	(26		)	(25		)
Other	(2		)	(8		)	—			—
Benefit obligation at end of year	$	4,150		$	4,025		$	224		$	264

Change in plan assets:
Fair value of plan assets at beginning of year	$	3,097		$	3,173		$	—		$	—
Actual return on plan assets	331			165			—			—
Employer contributions	162			52			—			—
Asset transfers	(2		)	(8		)	—			—
Benefits paid	(281		)	(285		)	—			—
Fair value of plan assets at end of year	$	3,307		$	3,097		$	—		$	—

Funded status at end of year	$	(843	)	$	(928	)	$	(224	)	$	(264	)



Net amounts recognized in the consolidated balance sheets at Dec 31:
Accrued and other current liabilities	$	(2	)	$	(2	)	$	(15	)	$	(24	)
Pension and other postretirement benefits - noncurrent	(841		)	(926		)	(209		)	(240		)
Net amount recognized	$	(843	)	$	(928	)	$	(224	)	$	(264	)

Pretax amounts recognized in accumulated other comprehensive (income) loss at Dec 31:
Net loss (gain)	$	2,083		$	2,035		$	(86	)	$	(69	)
Prior service credit	(12		)	(13		)	—			—
Pretax balance in accumulated other comprehensive (income) loss at end of year	$	2,071		$	2,022		$	(86	)	$	(69	)

Schedule of Projected Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]



Pension Plans with Projected Benefit Obligations in Excess of Plan Assets at Dec 31	2017		2016
In millions	2017		2016
Projected benefit obligations	$	4,150	$	4,025
Accumulated benefit obligations	$	4,120	$	3,997
Fair value of plan assets	$	3,307	$	3,097

Schedule of Net Benefit Costs [Table Text Block]



Net Periodic Benefit Cost for All Plans for the Year Ended Dec 31	Defined Benefit Pension Plans									Other Postretirement Benefits
	Defined Benefit Pension Plans									Other Postretirement Benefits
In millions	2017			2016			2015			2017			2016			2015
Net Periodic Benefit Cost:
Service cost	$	38		$	39		$	44		$	1		$	1		$	1
Interest cost	129			131			164			8			8			10
Expected return on plan assets	(221		)	(217		)	(226		)	—			—			—
Amortization of prior service credit	(1		)	(1		)	(1		)	—			—			(1		)
Amortization of net (gain) loss	83			75			87			(6		)	(7		)	(10		)
Net periodic benefit cost	$	28		$	27		$	68		$	3		$	2		$	—
Changes in plan assets and benefit obligations recognized in other comprehensive (income) loss:
Net (gain) loss	$	131		$	208		$	34		$	(23	)	$	4		$	19
Prior service cost	—			—			4			—			—			—
Amortization of prior service credit	1			1			1			—			—			1
Amortization of net gain (loss)	(83		)	(75		)	(87		)	6			7			10
Total recognized in other comprehensive (income) loss	$	49		$	134		$	(48	)	$	(17	)	$	11		$	30
Total recognized in net periodic benefit cost and other comprehensive (income) loss	$	77		$	161		$	20		$	(14	)	$	13		$	30

Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year [Table Text Block]

The estimated pretax net (gain) loss and prior service credit for defined benefit pension plans and other postretirement benefit plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost during 2018 are summarized below:



Estimated Pretax Amortization of Net (Gain) Loss and Prior Service Credit for the Year Ended Dec 31	2018
In millions	2018
Defined Benefit Pension Plans:
Net loss	$	95
Prior service credit	$	(1	)
Other Postretirement Benefit Plans:
Net gain	$	(9	)

Schedule of Expected Benefit Payments [Table Text Block]

The estimated future benefit payments, reflecting expected future service, as appropriate, are presented in the following table:



Estimated Future Benefit Payments at Dec 31, 2017	Defined Benefit Pension Plans		Other Postretirement Benefits
In millions	Defined Benefit Pension Plans		Other Postretirement Benefits
2018	$	275	$	16
2019	275		17
2020	274		17
2021	274		18
2022	272		19
2023-2027	1,307		79
Total	$	2,677	$	166

Schedule of Allocation of Plan Assets [Table Text Block]

The weighted-average target allocation for plan assets of the Corporation's pension plans is summarized as follows:



Target Allocation for Plan Assets at Dec 31, 2017	Target Allocation
Asset Category	Target Allocation
Equity securities	23	%
Fixed income securities	45
Alternative investments	27
Other	5
Total	100	%

Schedule of Defined Benefit Plans Disclosures [Table Text Block]

The following table summarizes the bases used to measure the Corporation’s pension plan assets at fair value for the years ended December 31, 2017 and 2016:



Basis of Fair Value Measurements	Dec 31, 2017										Dec 31, 2016 ¹
In millions	Total			Level 1		Level 2			Level 3		Total			Level 1		Level 2			Level 3
Cash and cash equivalents	$	193		$	153	$	40		$	—	$	242		$	237	$	5		$	—
Equity securities:
U.S. equity securities	$	374		$	357	$	17		$	—	$	253		$	236	$	17		$	—
Non - U.S. equity securities	472			404		61			7		294			234		54			6
Total equity securities	$	846		$	761	$	78		$	7	$	547		$	470	$	71		$	6
Fixed income securities:
Debt - government-issued	$	873		$	—	$	873		$	—	$	893		$	—	$	893		$	—
Debt - corporate-issued	515			—		515			—		512			—		512			—
Debt - asset-backed	24			—		24			—		33			—		33			—
Total fixed income securities	$	1,412		$	—	$	1,412		$	—	$	1,438		$	—	$	1,438		$	—
Alternative investments:
Hedge funds	$	292		$	—	$	124		$	168	$	341		$	21	$	139		$	181
Private market securities	237			—		—			237		214			—		—			214
Real estate	360			—		—			360		329			—		—			329
Derivatives - asset position	6			—		6			—		55			—		55			—
Derivatives - liability position	(32		)	—		(32		)	—		(66		)	—		(66		)	—
Total alternative investments	$	863		$	—	$	98		$	765	$	873		$	21	$	128		$	724
Other investments	$	(6	)	$	—	$	(6	)	$	—	$	18		$	—	$	(1	)	$	19
Subtotal	$	3,308		$	914	$	1,622		$	772	$	3,118		$	728	$	1,641		$	749
Items to reconcile to fair value of plan assets:
Pension trust receivables ²	$	2									$	4
Pension trust payables ³	(3		)								(25		)
Total	$	3,307									$	3,097

As a result of the DowDuPont merger, certain asset categories and classifications of prior period amounts have been revised to improve comparability with the presentation of Dow and DowDuPont, including the reclassification of cash and cash equivalents of $237 million, equity securities of $124 million and alternative investments of $21 million from Level 2 to Level 1. Further, pension trust receivables and pension trust payables previously presented with Level 2 investments are now separately presented.


2.	Primarily receivables for investment securities sold.


3.	Primarily payables for investment securities purchased.

Defined Benefit Pension Plans [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Assumptions Used [Table Text Block]



Pension Plan Assumptions	Benefit Obligations at Dec 31				Net Periodic Costs for the Year Ended
	2017		2016		2017		2016		2015
Discount rate	3.59	%	4.00	%	4.00	%	4.26	%	3.90	%
Rate of compensation increase	4.25	%	4.25	%	4.25	%	4.50	%	4.50	%
Expected return on plan assets	—		—		6.80	%	6.80	%	6.80	%

Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]



Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets at Dec 31
In millions	2017		2016
Projected benefit obligations	$	4,150	$	4,025
Accumulated benefit obligations	$	4,120	$	3,997
Fair value of plan assets	$	3,307	$	3,097

Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block]

The following table summarizes the changes in fair value of Level 3 pension plan assets for the years ended December 31, 2017 and 2016:



Fair Value Measurement of Level 3 Pension Plan Assets ¹	Equity Securities		Alternative Investments			Other Investments			Total
In millions	Equity Securities		Alternative Investments			Other Investments			Total
Balance at Jan 1, 2016	$	5	$	720		$	22		$	747
Actual return on plan assets:
Relating to assets held at Dec 31, 2016	1		(37		)	2			(34		)
Relating to assets sold during 2016	—		39			(8		)	31
Purchases, sales and settlements	—		2			3			5
Balance at Dec 31, 2016	$	6	$	724		$	19		$	749
Actual return on plan assets:
Relating to assets held at Dec 31, 2017	—		4			—			4
Relating to assets sold during 2017	—		25			—			25
Purchases, sales and settlements	1		12			(19		)	(6		)
Balance at Dec 31, 2017	$	7	$	765		$	—		$	772


1.	As a result of the DowDuPont merger, certain classifications of prior period amounts have been revised to improve comparability with the presentation of Dow and DowDuPont, including the reclassification of $77 million at December 31, 2016 ($51 million at December 31, 2015) of assets from fixed income securities to alternative investments.

Other Postretirement Benefits Plan [Member]

Defined Benefit Plan Disclosure [Line Items]

Schedule of Assumptions Used [Table Text Block]



Plan Assumptions for Other Postretirement Benefits	Benefit Obligations at Dec 31				Net Periodic Costs for the Year Ended
	2017		2016		2017		2016		2015
Discount rate	3.51	%	3.88	%	3.88	%	4.08	%	3.75	%
Health care cost trend rate assumed for next year	6.75	%	7.00	%	7.00	%	7.25	%	7.05	%
Rate to which the cost trend rate is assumed to decline (the ultimate health care cost trend rate)	5.00	%	5.00	%	5.00	%	5.00	%	5.00	%
Year that the rate reaches the ultimate health care cost trend rate	2025		2025		2025		2025		2020