Accounting and Disclosure Changes	9 Months Ended
Sep. 30, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Accounting and Disclosure Changes	Accounting and Disclosure Changes In January 2019, Occidental adopted the new lease standard Accounting Standards Codification Topic 842 - Leases (ASC 842). The new standard requires Occidental to recognize most leases, including operating leases, on the balance sheet. The new rules require lessees to recognize a right-of-use asset (ROU) and lease liability for all leases with lease terms of more than 12 months. Occidental adopted the standard using the modified retrospective approach, including adopting several optional practical expedients. See Note 10 - Lease Commitments.

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-URI http://asc.fasb.org/topic&trid=2122394

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