Changes in Accounting Principles	12 Months Ended
Dec. 31, 2016
Changes in Accounting Principles [Abstract]
Changes in Accounting Principles	Changes in Accounting Principles Effective January 1, 2016, we early adopted the Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU) No. 2015-17, “Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes.” This ASU simplified the presentation of deferred income taxes and required deferred tax liabilities and assets to be classified as noncurrent in a classified statement of financial position. The classification is made at the taxpaying component level of an entity, after reflecting any offset of deferred tax liabilities, deferred tax assets and any related valuation allowances. We applied this ASU prospectively to all deferred tax liabilities and assets. In June 2014, the FASB issued ASU No. 2014-10, “Development Stage Entities (Topic 915): Elimination of Certain Financial Reporting Requirements, Including an Amendment to Variable Interest Entities Guidance in Topic 810, Consolidation.” This ASU removed the definition of a development stage entity from the Master Glossary of the Accounting Standard Codification (ASC) and the related financial reporting requirements specific to development stage entities. ASU 2014-10 is intended to reduce cost and complexity of financial reporting for entities that have not commenced planned principal operations. For financial reporting requirements other than the variable interest entity (VIE) guidance in ASC Topic 810, ASU No. 2014-10 was effective for annual and quarterly reporting periods of public entities beginning after December 15, 2014. For the financial reporting requirements related to VIEs in ASC Topic 810, ASU No. 2014-10 was effective for annual and quarterly reporting periods of public entities beginning after December 15, 2015. We adopted the provisions of this ASU related to the financial reporting requirements other than the VIE guidance effective January 1, 2015. We adopted the remaining provisions effective January 1, 2016, and updated our disclosures about the risks and uncertainties related to our joint venture entities that have not commenced their principal operations.

Changes in Accounting Principles

Effective January 1, 2016, we early adopted the Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU) No. 2015-17, “Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes.” This ASU simplified the presentation of deferred income taxes and required deferred tax liabilities and assets to be classified as noncurrent in a classified statement of financial position. The classification is made at the taxpaying component level of an entity, after reflecting any offset of deferred tax liabilities, deferred tax assets and any related valuation allowances. We applied this ASU prospectively to all deferred tax liabilities and assets.

In June 2014, the FASB issued ASU No. 2014-10, “Development Stage Entities (Topic 915): Elimination of Certain Financial Reporting Requirements, Including an Amendment to Variable Interest Entities Guidance in Topic 810, Consolidation.” This ASU removed the definition of a development stage entity from the Master Glossary of the Accounting Standard Codification (ASC) and the related financial reporting requirements specific to development stage entities. ASU 2014-10 is intended to reduce cost and complexity of financial reporting for entities that have not commenced planned principal operations. For financial reporting requirements other than the variable interest entity (VIE) guidance in ASC Topic 810, ASU No. 2014-10 was effective for annual and quarterly reporting periods of public entities beginning after December 15, 2014. For the financial reporting requirements related to VIEs in ASC Topic 810, ASU No. 2014-10 was effective for annual and quarterly reporting periods of public entities beginning after December 15, 2015. We adopted the provisions of this ASU related to the financial reporting requirements other than the VIE guidance effective January 1, 2015. We adopted the remaining provisions effective January 1, 2016, and updated our disclosures about the risks and uncertainties related to our joint venture entities that have not commenced their principal operations.