Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2021	Jan. 31, 2022	Jun. 30, 2021
Entity Information [Line Items]
Entity File Number	001-38646
Entity Registrant Name	Dow Inc.
Entity Tax Identification Number	30-1128146
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Incorporation, State or Country Code	DE
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001751788
Current Fiscal Year End Date	--12-31
Entity Public Float			$ 47,100,000,000
ICFR Auditor Attestation Flag	true
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Document Information [Line Items]
Document Period End Date	Dec. 31, 2021
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Entity Shell Company	false
Entity Interactive Data Current	Yes
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	Midland, Michigan
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	DOW
Security Exchange Name	NYSE
Entity Listing, Par Value Per Share	$ 0.01
Entity Common Stock, Shares Outstanding		735,747,193
Entity Addresses [Line Items]
Entity Address, Address Line One	2211 H.H. Dow Way
Entity Address, City or Town	Midland
Entity Address, State or Province	MI
Entity Address, Postal Zip Code	48674
City Area Code	989
Local Phone Number	636-1000
Auditor Firm ID	34
The Dow Chemical Company
Entity Information [Line Items]
Entity File Number	001-03433
Entity Registrant Name	The Dow Chemical Company
Entity Tax Identification Number	38-1285128
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Incorporation, State or Country Code	DE
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000029915
Current Fiscal Year End Date	--12-31
ICFR Auditor Attestation Flag	true
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Document Information [Line Items]
Document Period End Date	Dec. 31, 2021
Document Type	10-K
Document Annual Report	true
Document Transition Report	false
Entity Shell Company	false
Entity Interactive Data Current	Yes
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Listings [Line Items]
Security Exchange Name	NYSE
Entity Listing, Par Value Per Share	$ 0.01
Entity Common Stock, Shares Outstanding		100
Entity Addresses [Line Items]
Entity Address, Address Line One	2211 H.H. Dow Way
Entity Address, City or Town	Midland
Entity Address, State or Province	MI
Entity Address, Postal Zip Code	48674
City Area Code	989
Local Phone Number	636-1000
0.500% Notes due March 15, 2027 [Member] | The Dow Chemical Company
Entity Listings [Line Items]
Title of 12(b) Security	0.500% Notes due March 15, 2027
Trading Symbol	DOW/27
1.125% Notes due March 15, 2032 [Member] | The Dow Chemical Company
Entity Listings [Line Items]
Title of 12(b) Security	1.125% Notes due March 15, 2032
Trading Symbol	DOW/32
1.875% Notes due March 15, 2040 [Member] | The Dow Chemical Company
Entity Listings [Line Items]
Title of 12(b) Security	1.875% Notes due March 15, 2040
Trading Symbol	DOW/40
4.625% Notes due October 1, 2044 [Member] | The Dow Chemical Company
Entity Listings [Line Items]
Title of 12(b) Security	4.625% Notes due October 1, 2044
Trading Symbol	DOW/44