TDCC Consolidated Balance Sheets Parentheticals - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Cash and cash equivalents (variable interest entities restricted - 2021: $37; 2020: $26)	$ 4,133	$ 5,104
Accounts Receivable, Allowance for Credit Loss, Current	55	51
Investments, Fair Value Disclosure	1,529	1,674
Net property (variable interest entities restricted - 2021: $216; 2020: $232)	19,897	20,239
Finite-Lived Intangible Assets, Accumulated Amortization	4,521	4,428
Long-Term Debt (variable interest entities nonrecourse - 2021: $6; 2020: $6)	$ 16,200	$ 16,491
Common Stock, Shares, Issued	759,792,745	755,993,198
Common Stock, Shares Authorized	5,000,000,000	5,000,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
The Dow Chemical Company [Domain]
Cash and cash equivalents (variable interest entities restricted - 2021: $37; 2020: $26)	$ 4,133	$ 5,104
Accounts Receivable, Allowance for Credit Loss, Current	55	51
Net property (variable interest entities restricted - 2021: $216; 2020: $232)	19,897	20,239
Finite-Lived Intangible Assets, Accumulated Amortization	4,521	4,428
Long-Term Debt (variable interest entities nonrecourse - 2021: $6; 2020: $6)	$ 16,200	$ 16,491
Common Stock, Shares, Issued	100	100
Common Stock, Shares Authorized	100	100
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Variable Interest Entity, Primary Beneficiary [Member]
Cash and cash equivalents (variable interest entities restricted - 2021: $37; 2020: $26)	$ 37	$ 26
Net property (variable interest entities restricted - 2021: $216; 2020: $232)	216	232
Long-Term Debt (variable interest entities nonrecourse - 2021: $6; 2020: $6)	$ 6	$ 6