Income Taxes	6 Months Ended
Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Taxes on income for the second quarter and first six months of 2016 benefited earnings by $0.6 billion and $1.6 billion, respectively, compared with charges of $0.8 billion and $1.1 billion, respectively for the corresponding periods in 2015. The associated effective tax rates (calculated as the amount of Income Tax Expense (Benefit) divided by Income (Loss) Before Income Tax Expense) for the second quarters of 2016 and 2015 were 29 percent and 55 percent, respectively. For the comparative six-month periods the effective tax rates were 43 percent and 25 percent, respectively. Excluding the effects of equity earnings, the effective tax rates for the 2016 and 2015 quarterly periods were 24 percent and 334 percent, respectively, a decrease of 310 percent between periods, and the tax rates for the respective six-month periods were 34 percent and 50 percent, a decrease of 16 percent between periods. The decrease in the effective tax rate between the quarterly periods primarily resulted from the effects of valuation allowances recognized on deferred tax assets, the absence of the 2015 sale of the company's interest in Caltex Australia Limited and foreign currency remeasurement effects, partially offset by jurisdictional mix impacts. The decrease in the effective tax rate for the six-month comparative period primarily resulted from the effects of valuation allowances recognized on deferred tax assets and the absence of the 2015 sale of the company's interest in Caltex Australia Limited, partially offset by jurisdictional mix impacts. Tax positions for Chevron and its subsidiaries and affiliates are subject to income tax audits by many tax jurisdictions throughout the world. For the company’s major tax jurisdictions, examinations of tax returns for certain prior tax years had not been completed as of June 30, 2016. For these jurisdictions, the latest years for which income tax examinations had been finalized were as follows: United States — 2011, Nigeria — 2000, Angola — 2009 and Kazakhstan — 2007. The company engages in ongoing discussions with tax authorities regarding the resolution of tax matters in the various jurisdictions. Both the outcomes for these tax matters and the timing of resolution and/or closure of the tax audits are highly uncertain. However, it is reasonably possible that developments regarding tax matters in certain tax jurisdictions may result in significant increases or decreases in the company’s total unrecognized tax benefits within the next 12 months. Given the number of years that still remain subject to examination and the number of matters being examined in the various tax jurisdictions, the company is unable to estimate the range of possible adjustments to the balance of unrecognized tax benefits. Effective January 1, 2016, Chevron early-adopted Income Taxes (Topic 740), Balance Sheet Classification of Deferred Taxes (ASU 2015-17), on a retrospective basis. The standard provides that all deferred income taxes be classified as noncurrent on the Consolidated Balance Sheet. The prior requirement was to classify most deferred tax assets and liabilities based on the classification of the underlying asset or liability. The effects of retrospective adoption on the December 31, 2015, Consolidated Balance Sheet were reductions of $917 million in "Prepaid expenses and other current assets," $603 million in "Deferred charges and other assets," $996 million in "Federal and other taxes on income," and $524 million in "Noncurrent deferred income taxes."

Income Taxes

Taxes on income for the second quarter and first six months of 2016 benefited earnings by $0.6 billion and $1.6 billion, respectively, compared with charges of $0.8 billion and $1.1 billion, respectively for the corresponding periods in 2015. The associated effective tax rates (calculated as the amount of Income Tax Expense (Benefit) divided by Income (Loss) Before Income Tax Expense) for the second quarters of 2016 and 2015 were 29 percent and 55 percent, respectively. For the comparative six-month periods the effective tax rates were 43 percent and 25 percent, respectively.

Excluding the effects of equity earnings, the effective tax rates for the 2016 and 2015 quarterly periods were 24 percent and 334 percent, respectively, a decrease of 310 percent between periods, and the tax rates for the respective six-month periods were 34 percent and 50 percent, a decrease of 16 percent between periods. The decrease in the effective tax rate between the quarterly periods primarily resulted from the effects of valuation allowances recognized on deferred tax assets, the absence of the 2015 sale of the company's interest in Caltex Australia Limited and foreign currency remeasurement effects, partially offset by jurisdictional mix impacts. The decrease in the effective tax rate for the six-month comparative period primarily resulted from the effects of valuation allowances recognized on deferred tax assets and the absence of the 2015 sale of the company's interest in Caltex Australia Limited, partially offset by jurisdictional mix impacts.

Tax positions for Chevron and its subsidiaries and affiliates are subject to income tax audits by many tax jurisdictions throughout the world. For the company’s major tax jurisdictions, examinations of tax returns for certain prior tax years had not been completed as of June 30, 2016. For these jurisdictions, the latest years for which income tax examinations had been finalized were as follows: United States — 2011, Nigeria — 2000, Angola — 2009 and Kazakhstan — 2007.

The company engages in ongoing discussions with tax authorities regarding the resolution of tax matters in the various jurisdictions. Both the outcomes for these tax matters and the timing of resolution and/or closure of the tax audits are highly uncertain. However, it is reasonably possible that developments regarding tax matters in certain tax jurisdictions may result in significant increases or decreases in the company’s total unrecognized tax benefits within the next 12 months. Given the number of years that still remain subject to examination and the number of matters being examined in the various tax jurisdictions, the company is unable to estimate the range of possible adjustments to the balance of unrecognized tax benefits.

Effective January 1, 2016, Chevron early-adopted Income Taxes (Topic 740), Balance Sheet Classification of Deferred Taxes (ASU 2015-17), on a retrospective basis. The standard provides that all deferred income taxes be classified as noncurrent on the Consolidated Balance Sheet. The prior requirement was to classify most deferred tax assets and liabilities based on the classification of the underlying asset or liability. The effects of retrospective adoption on the December 31, 2015, Consolidated Balance Sheet were reductions of $917 million in "Prepaid expenses and other current assets," $603 million in "Deferred charges and other assets," $996 million in "Federal and other taxes on income," and $524 million in "Noncurrent deferred income taxes."