CONSOLIDATED FINANCIAL STATEMENTS	3 Months Ended
Mar. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
CONSOLIDATED FINANCIAL STATEMENTS	CONSOLIDATED FINANCIAL STATEMENTS Basis of Presentation The unaudited interim consolidated financial statements of Union Carbide Corporation and its subsidiaries (the "Corporation" or "UCC") were prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") and reflect all adjustments (including normal recurring accruals) which, in the opinion of management, are considered necessary for the fair presentation of the results for the periods presented. These statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2018. The Corporation is a wholly owned subsidiary of The Dow Chemical Company ("TDCC"). In accordance with the accounting guidance for earnings per share, the presentation of earnings per share is not required in financial statements of wholly owned subsidiaries. The Corporation’s business activities comprise components of TDCC’s global operations rather than stand-alone operations. TDCC conducts its worldwide operations through principal product groups. Because there are no separable reportable business segments for UCC under the accounting guidance related to segment reporting and no detailed business information is provided to a chief operating decision maker regarding the Corporation’s stand-alone operations, the Corporation’s results are reported as a single operating segment. Effective August 31, 2017, pursuant to the merger of equals transaction contemplated by the Agreement and Plan of Merger, dated as of December 11, 2015, as amended on March 31, 2017, TDCC and its consolidated subsidiaries and E. I. du Pont de Nemours and Company and its consolidated subsidiaries ("DuPont") each merged with subsidiaries of DowDuPont Inc. ("DowDuPont") and, as a result, TDCC and DuPont became subsidiaries of DowDuPont (the "Merger"). Subsequent to the Merger, TDCC and DuPont engaged in a series of internal reorganization and realignment steps to realign their businesses into three subgroups: agriculture, materials science and specialty products. Dow Inc. was formed as a wholly owned subsidiary of DowDuPont to serve as a holding company for the materials science business. On April 1, 2019, DowDuPont completed the separation of its materials science business and Dow Inc. became the direct parent company of TDCC. UCC will continue to be a wholly owned subsidiary of TDCC. See Note 3 for additional information. Intercompany transactions and balances are eliminated in consolidation. Transactions with the Corporation’s parent company, TDCC, and other subsidiaries of TDCC and DowDuPont, have been reflected as related company transactions in the consolidated financial statements. See Note 13 for additional information. Adoption of Accounting Standards In the first quarter of 2019, UCC adopted Accounting Standards Update ("ASU") 2016-02, "Leases (Topic 842)," and associated ASUs related to Topic 842. See Notes 2 and 9 for additional information. UCC added a significant accounting policy for leases as a result of the adoption of Topic 842: Leases UCC determines whether a contract contains a lease at contract inception. A contract contains a lease if there is an identified asset and the Corporation has the right to control the asset. Operating lease right-of-use (“ROU”) assets represent UCC’s right to use an underlying asset for the lease term, and lease liabilities represent UCC’s obligation to make lease payments arising from the lease. Operating lease ROU assets and lease liabilities are recognized at commencement date based on the present value of lease payments over the lease term. UCC uses the incremental borrowing rate (“IBR”) in determining the present value of lease payments, unless the implicit rate is readily determinable. If lease terms include options to extend or terminate the lease, the ROU asset and lease liability are measured based on the reasonably certain decision. Leases with a term of 12 months or less at the commencement date are not recognized on the balance sheet and are expensed as incurred. UCC has lease agreements with lease and non-lease components, which are accounted for as a single lease component for all classes of leased assets for which UCC is the lessee. Additionally, for certain equipment leases, the portfolio approach is applied to account for the operating lease ROU assets and lease liabilities. In the consolidated statements of income, lease expense for operating lease payments is recognized on a straight-line basis over the lease term. For finance leases, interest expense is recognized on the lease liability and the ROU asset is amortized over the lease term. Some leasing arrangements require variable payments that are dependent upon usage or output, or may vary for other reasons, such as insurance or tax payments. Variable lease payments are recognized as incurred and are not presented as part of the ROU asset or lease liability.

CONSOLIDATED FINANCIAL STATEMENTS

Basis of Presentation

The unaudited interim consolidated financial statements of Union Carbide Corporation and its subsidiaries (the "Corporation" or "UCC") were prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") and reflect all adjustments (including normal recurring accruals) which, in the opinion of management, are considered necessary for the fair presentation of the results for the periods presented. These statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2018.

The Corporation is a wholly owned subsidiary of The Dow Chemical Company ("TDCC"). In accordance with the accounting guidance for earnings per share, the presentation of earnings per share is not required in financial statements of wholly owned subsidiaries.

The Corporation’s business activities comprise components of TDCC’s global operations rather than stand-alone operations. TDCC conducts its worldwide operations through principal product groups. Because there are no separable reportable business segments for UCC under the accounting guidance related to segment reporting and no detailed business information is provided to a chief operating decision maker regarding the Corporation’s stand-alone operations, the Corporation’s results are reported as a single operating segment.

Effective August 31, 2017, pursuant to the merger of equals transaction contemplated by the Agreement and Plan of Merger, dated as of December 11, 2015, as amended on March 31, 2017, TDCC and its consolidated subsidiaries and E. I. du Pont de Nemours and Company and its consolidated subsidiaries ("DuPont") each merged with subsidiaries of DowDuPont Inc. ("DowDuPont") and, as a result, TDCC and DuPont became subsidiaries of DowDuPont (the "Merger"). Subsequent to the Merger, TDCC and DuPont engaged in a series of internal reorganization and realignment steps to realign their businesses into three subgroups: agriculture, materials science and specialty products. Dow Inc. was formed as a wholly owned subsidiary of DowDuPont to serve as a holding company for the materials science business. On April 1, 2019, DowDuPont completed the separation of its materials science business and Dow Inc. became the direct parent company of TDCC. UCC will continue to be a wholly owned subsidiary of TDCC. See Note 3 for additional information.

Intercompany transactions and balances are eliminated in consolidation. Transactions with the Corporation’s parent company, TDCC, and other subsidiaries of TDCC and DowDuPont, have been reflected as related company transactions in the consolidated financial statements. See Note 13 for additional information.

Adoption of Accounting Standards

In the first quarter of 2019, UCC adopted Accounting Standards Update ("ASU") 2016-02, "Leases (Topic 842)," and associated ASUs related to Topic 842. See Notes 2 and 9 for additional information. UCC added a significant accounting policy for leases as a result of the adoption of Topic 842:

Leases

UCC determines whether a contract contains a lease at contract inception. A contract contains a lease if there is an identified asset and the Corporation has the right to control the asset.

Operating lease right-of-use (“ROU”) assets represent UCC’s right to use an underlying asset for the lease term, and lease liabilities represent UCC’s obligation to make lease payments arising from the lease. Operating lease ROU assets and lease liabilities are recognized at commencement date based on the present value of lease payments over the lease term. UCC uses the incremental borrowing rate (“IBR”) in determining the present value of lease payments, unless the implicit rate is readily determinable. If lease terms include options to extend or terminate the lease, the ROU asset and lease liability are measured based on the reasonably certain decision. Leases with a term of 12 months or less at the commencement date are not recognized on the balance sheet and are expensed as incurred.

UCC has lease agreements with lease and non-lease components, which are accounted for as a single lease component for all classes of leased assets for which UCC is the lessee. Additionally, for certain equipment leases, the portfolio approach is applied to account for the operating lease ROU assets and lease liabilities. In the consolidated statements of income, lease expense for operating lease payments is recognized on a straight-line basis over the lease term. For finance leases, interest expense is recognized on the lease liability and the ROU asset is amortized over the lease term.

Some leasing arrangements require variable payments that are dependent upon usage or output, or may vary for other reasons, such as insurance or tax payments. Variable lease payments are recognized as incurred and are not presented as part of the ROU asset or lease liability.