Organization and Basis of Presentation Effect of New Accounting Standards (Policies)	3 Months Ended
Mar. 31, 2015
New Accounting Policies [Abstract]
New Accounting Pronouncements, Policy [Policy Text Block]	Effect of New Accounting Standards On April 7, 2015, the Financial Accounting Standards Board (FASB) issued an accounting standards update (ASU) which changes the presentation of debt issuance costs in financial statements. Under the ASU, an entity would present such costs in the balance sheet as a direct deduction of the related debt liability rather than as an asset. Amortization of the costs will continue to be reported as interest expense. This ASU becomes effective for AAM at the beginning of our 2016 fiscal year and early adoption is permitted. We estimate the effect of implementing this ASU on our consolidated financial statements would reduce both our other assets and deferred charges and long-term debt by approximately $15.5 million at December 31, 2015. In 2014, new accounting guidance was issued that outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The guidance is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. This guidance becomes effective for AAM at the beginning of our 2017 fiscal year, however on April 1, 2015, the FASB proposed to defer the effective date of this revenue recognition guidance by one year. We are currently assessing the impact that this standard will have on our consolidated financial statements.

Effect of New Accounting Standards On April 7, 2015, the Financial Accounting Standards Board (FASB) issued an accounting standards update (ASU) which changes the presentation of debt issuance costs in financial statements. Under the ASU, an entity would present such costs in the balance sheet as a direct deduction of the related debt liability rather than as an asset. Amortization of the costs will continue to be reported as interest expense. This ASU becomes effective for AAM at the beginning of our 2016 fiscal year and early adoption is permitted. We estimate the effect of implementing this ASU on our consolidated financial statements would reduce both our other assets and deferred charges and long-term debt by approximately $15.5 million at December 31, 2015.

In 2014, new accounting guidance was issued that outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The guidance is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. This guidance becomes effective for AAM at the beginning of our 2017 fiscal year, however on April 1, 2015, the FASB proposed to defer the effective date of this revenue recognition guidance by one year. We are currently assessing the impact that this standard will have on our consolidated financial statements.