Basis of Presentation Basis of Presentation (Notes)	6 Months Ended
Jun. 30, 2015
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation We prepared the accompanying unaudited consolidated financial statements in accordance with US Generally Accepted Accounting Principles ("GAAP") for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, our unaudited consolidated financial statements do not include all of the information and footnotes required for complete financial statements. We have included all of the normal recurring adjustments that we deemed necessary for a fair presentation. Operating results for the six months ended June 30, 2015, are not necessarily indicative of the results we may achieve for the entire year ending December 31, 2015. In particular, ASC's fleet is inactive for a significant portion of the first quarter of each year due to winter conditions on the Great Lakes. In addition, asset remarketing income does not occur evenly throughout the year. For more information, refer to the consolidated financial statements and footnotes in our Annual Report on Form 10-K for the year ended December 31, 2014. Accounting Changes Discontinued Operations In April 2014, the Financial Accounting Standards Board ("FASB") issued amendments to authoritative guidance for reporting discontinued operations and disposals of components of an entity. The amendments require that disposals representing strategic shifts that have (or will have) a major effect on an entity’s operations or financial results should be reported as discontinued operations. The amendments also expand the disclosure requirements for both discontinued operations and significant dispositions that do not qualify as discontinued operations. The amendments were effective for us beginning in the first quarter of 2015. Adoption of the new guidance did not impact the amount or timing of net income or the presentation and disclosures of our financial statements. New Accounting Pronouncements Debt Issue Costs In April 2015, the FASB issued authoritative guidance that requires presentation of debt issue costs as a deduction from the carrying amount of the related debt liability on the balance sheet, rather than as a deferred charge. The new guidance is effective for us beginning in the first quarter of 2016, with early adoption permitted. Adoption of the new guidance is not expected to impact the amount or timing of net income but may result in changes to the presentation and disclosures of our financial statements. Consolidation In February 2015, the FASB issued authoritative guidance amending the analysis required to determine whether to consolidate certain types of legal entities such as limited partnerships, limited liability corporations, and certain securitization structures. The new guidance is effective for us beginning in the first quarter of 2016, with early adoption permitted. We are currently evaluating the effect, if any, the new guidance will have on our financial statements and related disclosures. Revenue from Contracts with Customers In May 2014, the FASB issued authoritative accounting guidance that supersedes most current revenue recognition guidance, including industry-specific guidance. The new guidance requires companies to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration it expects to be entitled to in exchange for those goods or services. In July 2015, the FASB deferred the effective date of this standard from the first quarter of 2017 to the first quarter of 2018. Early adoption is permitted as of the original effective date. We can adopt the new guidance using either the retrospective method or the cumulative effect transition method. We are still evaluating the effect that the new guidance will have on our consolidated financial statements and related disclosures, including which transition method we will use and when we will choose to adopt this standard.

Basis of Presentation

We prepared the accompanying unaudited consolidated financial statements in accordance with US Generally Accepted Accounting Principles ("GAAP") for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, our unaudited consolidated financial statements do not include all of the information and footnotes required for complete financial statements. We have included all of the normal recurring adjustments that we deemed necessary for a fair presentation.

Operating results for the six months ended June 30, 2015, are not necessarily indicative of the results we may achieve for the entire year ending December 31, 2015. In particular, ASC's fleet is inactive for a significant portion of the first quarter of each year due to winter conditions on the Great Lakes. In addition, asset remarketing income does not occur evenly throughout the year. For more information, refer to the consolidated financial statements and footnotes in our Annual Report on Form 10-K for the year ended December 31, 2014.

Accounting Changes

Discontinued Operations

In April 2014, the Financial Accounting Standards Board ("FASB") issued amendments to authoritative guidance for reporting discontinued operations and disposals of components of an entity. The amendments require that disposals representing strategic shifts that have (or will have) a major effect on an entity’s operations or financial results should be reported as discontinued operations. The amendments also expand the disclosure requirements for both discontinued operations and significant dispositions that do not qualify as discontinued operations.

The amendments were effective for us beginning in the first quarter of 2015. Adoption of the new guidance did not impact the amount or timing of net income or the presentation and disclosures of our financial statements.

New Accounting Pronouncements

Debt Issue Costs

In April 2015, the FASB issued authoritative guidance that requires presentation of debt issue costs as a deduction from the carrying amount of the related debt liability on the balance sheet, rather than as a deferred charge. The new guidance is effective for us beginning in the first quarter of 2016, with early adoption permitted. Adoption of the new guidance is not expected to impact the amount or timing of net income but may result in changes to the presentation and disclosures of our financial statements.

Consolidation

In February 2015, the FASB issued authoritative guidance amending the analysis required to determine whether to consolidate certain types of legal entities such as limited partnerships, limited liability corporations, and certain securitization structures. The new guidance is effective for us beginning in the first quarter of 2016, with early adoption permitted. We are currently evaluating the effect, if any, the new guidance will have on our financial statements and related disclosures.

Revenue from Contracts with Customers

In May 2014, the FASB issued authoritative accounting guidance that supersedes most current revenue recognition guidance, including industry-specific guidance. The new guidance requires companies to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration it expects to be entitled to in exchange for those goods or services.

In July 2015, the FASB deferred the effective date of this standard from the first quarter of 2017 to the first quarter of 2018. Early adoption is permitted as of the original effective date. We can adopt the new guidance using either the retrospective method or the cumulative effect transition method. We are still evaluating the effect that the new guidance will have on our consolidated financial statements and related disclosures, including which transition method we will use and when we will choose to adopt this standard.