American Axle & Manufacturing (AXL) 10-K 7 Feb 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document (USD $)	12 Months Ended
	Dec. 31, 2013	Feb. 05, 2014	Jun. 30, 2013
Document Information [Line Items]	'	'	'
Entity Registrant Name	'AMERICAN AXLE & MANUFACTURING HOLDINGS INC	'	'
Entity Central Index Key	'0001062231	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Document Period End Date	31-Dec-13	'	'
Amendment Flag	'false	'	'
Document Type	'10-K	'	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Public Float	'	'	$1,278,146,286
Entity Common Stock, Shares Outstanding	'	75,598,824	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net sales	$3,207.30	$2,930.90	$2,585
Cost of goods sold	2,728.60	2,531.20	2,129.90
Gross profit	478.7	399.7	455.1
Selling, general and administrative expenses	238.4	243.3	231.7
Operating income	240.3	156.4	223.4
Interest expense	-115.9	-101.6	-83.9
Investment income	0.6	0.6	1.2
Other income (expense)	'	'	'
Debt refinancing and redemption costs	-36.8	-19.8	-3.1
Other, net	-1.9	-4.1	0.5
Income before income taxes	86.3	31.5	138.1
Income tax expense (benefit)	-8.2	-335.2	1
Net income	94.5	366.7	137.1
Net loss attributable to noncontrolling interests	0	1	5.7
Net income attributable to AAM	$94.50	$367.70	$142.80
Basic earnings per share	$1.23	$4.88	$1.91
Diluted earnings per share	$1.23	$4.87	$1.89

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net income	$94.50	$366.70	$137.10
Other comprehensive income (loss), net of tax [Abstract]	'	'	'
Defined benefit plans, net of $(41.3) million and $32.3 million of tax in 2013 and 2012, respectively	76.6	-58.9	-63.5
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	-26.2	-9.4	-27.3
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	-2	7.8	-6.8
Foreign currency translation adjustments	-26.2	'	'
Other comprehensive income (loss)	48.4	-60.5	-97.6
Comprehensive Income	142.9	306.2	39.5
Net loss attributable to noncontrolling interests	0	1	5.7
Foreign currency translation adjustments attributable to noncontrolling interests	0	0.3	0.2
Comprehensive income attributable to AAM	$142.90	$306.90	$45

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income Parenthetical (Parentheticals) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Other comprehensive income (loss), pension and other postretirement benefit plans, net unamortized (gain) loss arising during period, tax	($41.30)	$32.30

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Current Assets	'	'
Cash and cash equivalents	$154	$62.40
Accounts receivable, net	458.5	463.4
Inventories, net	261.8	224.3
Deferred income taxes	36.4	34.9
Prepaid expenses and other	87.1	87.1
Total current assets	997.8	872.1
Property, plant and equipment, net	1,058.50	1,009.70
Deferred income taxes	341.8	366.1
Goodwill	156.4	156.4
GM postretirement cost sharing asset	242	259.7
Other assets and deferred charges	232.5	202
Total assets	3,029	2,866
Current Liabilities	'	'
Accounts payable	445.8	396.1
Accrued compensation and benefits	110.1	84.9
Deferred revenue	17	17.2
Deferred income taxes	0.1	1.4
Other accrued expenses	94.1	101.2
Total current liabilities	667.1	600.8
Long-term debt	1,559.10	1,454.10
Deferred income taxes	9.8	9.5
Deferred revenue	76.4	82.2
Postretirement benefits and other long-term liabilities	683	840.2
Total liabilities	2,995.40	2,986.80
Stockholders' equity (deficit)	'	'
Series A junior participating preferred stock, par value $0.01 per share; 0.1 million shares authorized; no shares outstanding in 2013 or 2012	0	0
Preferred stock, par value $0.01 per share; 10.0 million shares authorized; no shares outstanding in 2013 or 2012	0	0
Common stock, par value $0.01 per share; 150.0 million shares authorized; 81.6 million and 80.9 million shares issued and outstanding in 2013 and 2012, respectively	0.8	0.8
Series common stock, par value $0.01 per share; 40.0 million shares authorized; no shares outstanding in 2013 or 2012	0	0
Paid-in capital	612.8	600.9
Accumulated deficit	-181.3	-275.8
Treasury stock at cost, 6.0 million shares in 2013 and 2012	-182.5	-182.1
Accumulated other comprehensive income (loss), net of tax	'	'
Defined benefit plans	-197.9	-274.5
Foreign currency translation adjustments	-18.6	7.6
Unrecognized gain on derivatives	0.3	2.3
Total AAM stockholders' equity (deficit)	33.6	-120.8
Noncontrolling interest in subsidiaries	0	0
Total stockholders’ equity (deficit)	33.6	-120.8
Total liabilities and stockholders' equity (deficit)	$3,029	$2,866

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets Parenthetical (Parentheticals) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, except Per Share data, unless otherwise specified
Series A Preferred Stock [Member]	'	'
Preferred stock, par or stated value per share	$0.01	$0.01
Preferred stock, shares authorized	0.1	0.1
Preferred stock, shares outstanding	0	0
Preferred Stock [Member]	'	'
Preferred stock, par or stated value per share	$0.01	$0.01
Preferred stock, shares authorized	10	10
Preferred stock, shares outstanding	0	0
Common Stock [Member]	'	'
Common stock, par or stated value per share	$0.01	$0.01
Common stock, shares authorized	150	150
Common stock, shares issued	81.6	80.9
Treasury stock, shares	6	6
Series Common Stock [Member]	'	'
Common stock, par or stated value per share	$0.01	$0.01
Common stock, shares authorized	40	40
Common stock, shares, outstanding	0	0

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating activities	'	'	'
Net income	$94.50	$366.70	$137.10
Adjustments to reconcile net income to cash provided by (used in) operating activities	'	'	'
Asset impairments and related indirect inventory obsolescence	0	5.8	8.7
Depreciation and amortization	177	152.2	139.4
Deferred income taxes	-18.7	-343.8	17.2
Stock-based compensation	10.8	2.4	4.5
Pensions and other postretirement benefits, net of contributions	6.5	-208.4	-33.3
Gain on retirement of equipment and held-for-sale assets, net	-3.5	-1.9	-6.9
Debt refinancing and redemption costs	9.2	1.5	1.8
Changes in operating assets and liabilities	'	'	'
Accounts receivable	-0.3	-130.6	-189.9
Inventories	-42.5	-49.9	-50.2
Accounts payable and accrued expenses	66.3	60.9	37.1
Deferred revenue	-5.6	-21.6	-74.7
Other assets and liabilities	-70.7	-8.8	-47.1
Net cash provided by (used in) operating activities	223	-175.5	-56.3
Investing activities	'	'	'
Purchases of property, plant and equipment	-251.9	-207.6	-163.1
Proceeds from sale of property, plant and equipment	9.1	10.1	8.9
Proceeds from sale-leaseback of equipment	24.1	12.1	0
Purchase buyouts of leased equipment	0	0	-13.4
Acquisition, net	0	0	-16.5
Net cash used in investing activities	-218.7	-185.4	-184.1
Financing activities	'	'	'
Net short-term borrowings (repayments) under credit facilities	-29.9	10.4	2.6
Proceeds from issuance of long-term debt	786.7	562.6	227
Payments of other long-term debt and capital lease obligations	-652	-299.1	-56
Debt issuance costs	-16.7	-10.6	-10.9
Purchase of noncontrolling interest	0	-4	0
Employee stock option exercises, including tax benefit	1.1	0.1	4.6
Purchase of treasury stock	-0.4	-5.9	-0.1
Net cash provided by financing activities	88.8	253.5	167.2
Effect of exchange rate changes on cash	-1.5	0.6	-2.2
Net increase (decrease) in cash and cash equivalents	91.6	-106.8	-75.4
Cash and cash equivalents at beginning of year	62.4	169.2	244.6
Cash and cash equivalents at end of year	154	62.4	169.2
Supplemental cash flow information	'	'	'
Interest paid	123.2	88.9	73.1
Income taxes paid, net	$11.60	$14.70	$10.90

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (USD $)	3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	'	'	($2)	$7.80	($6.80)	'
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	'	'	-26.2	-9.4	-27.3	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax	'	'	76.6	-58.9	-63.5	'
Paid-in capital	612.8	600.9	612.8	600.9	'	'
Accumulated deficit	-181.3	-275.8	-181.3	-275.8	'	'
Treasury stock	-182.5	-182.1	-182.5	-182.1	'	'
Accumulated other comprehensive income (loss), net of tax	-216.2	-264.6	-216.2	-264.6	'	'
Noncontrolling interest in subsidiaries	0	0	0	0	5.9	11.4
Net income attributable to AAM	29.8	319.9	94.5	367.7	142.8	'
Net loss attributable to noncontrolling interests	'	'	0	1	5.7	'
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	0	0.3	0.2	'
2008 GM agreement, shares issued to GM through exercise of warrants	'	'	'	'	3.3	'
Common Stock [Member]	'	'	'	'	'	'
Common stock, shares outstanding	75.6	74.8	75.6	74.8	73.8	68.8
Common stock, par value	0.8	0.8	0.8	0.8	0.8	0.8
Stock issued during period, exercise of stock options and vesting of restricted stock	'	'	0.8	1.5	1.7	'
Treasury stock, shares, acquired	'	'	0	-0.5	0	'
Additional Paid-in Capital [Member]	'	'	'	'	'	'
Paid-in capital	612.8	600.9	612.8	600.9	597.2	588.1
Change in additional paid in capital for exercise of stock options and vesting of restricted stock	'	'	1.1	0.1	4.6	'
Adjustments to additional paid in capital, stock based compensation	'	'	10.8	2.4	4.5	'
Retained Earnings [Member]	'	'	'	'	'	'
Accumulated deficit	-181.3	-275.8	-181.3	-275.8	-643.5	-786.3
Net income attributable to AAM	'	'	94.5	367.7	142.8	'
Treasury Stock [Member]	'	'	'	'	'	'
Treasury stock	-182.5	-182.1	-182.5	-182.1	-176.2	-176.1
Treasury stock, value, acquired, cost method	'	'	-0.4	-5.9	-0.1	'
Accumulated Other Comprehensive Income (Loss) [Member]	'	'	'	'	'	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	'	'	-2	7.8	-6.8	'
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	'	'	-26.2	-9.7	-27.5	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax	'	'	-76.6	58.9	63.5	'
Accumulated other comprehensive income (loss), net of tax	($216.20)	($264.60)	($216.20)	($264.60)	($203.80)	($106)

Organization_and_Basis_of_Pres

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2013
Organization and Basis of Presentation [Abstract]	'
Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block]	'
	1	ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	ORGANIZATION American Axle & Manufacturing Holdings, Inc. (Holdings) and its subsidiaries (collectively, we, our, us or AAM) is a Tier I supplier to the automotive industry. We manufacture, engineer, design and validate driveline and drivetrain systems and related components and chassis modules for light trucks, sport utility vehicles (SUVs), passenger cars, crossover vehicles and commercial vehicles. Driveline and drivetrain systems include components that transfer power from the transmission and deliver it to the drive wheels. Our driveline, drivetrain and related products include axles, chassis modules, driveshafts, power transfer units, transfer cases, chassis and steering components, driveheads, transmission parts and metal-formed products. In addition to locations in the United States (U.S.) (Michigan, Ohio, Indiana and Pennsylvania), we also have offices or facilities in Brazil, China, Germany, India, Japan, Luxembourg, Mexico, Poland, Scotland, South Korea, Sweden and Thailand.
	PRINCIPLES OF CONSOLIDATION We include the accounts of Holdings and its subsidiaries in our consolidated financial statements. We eliminate the effects of all intercompany transactions, balances and profits in our consolidation.
	REVENUE RECOGNITION We recognize revenue when products are shipped to our customers and title transfers under standard commercial terms or when realizable in accordance with our commercial agreements. If we are uncertain as to whether we will be successful collecting a balance in accordance with our understanding of a commercial agreement, we do not recognize the revenue or cost recovery until such time as the uncertainty is removed.
	In 2009, we entered into a settlement and commercial agreement (2009 Settlement and Commercial Agreement) with General Motors Company (GM). As part of this agreement, we received $110.0 million from GM, of which we recorded $79.7 million as deferred revenue.  As of December 31, 2013, our deferred revenue related to the 2009 Settlement and Commercial Agreement is $45.5 million, $8.0 million of which is classified as a current liability and $37.5 million of which is recorded as a noncurrent liability on our Consolidated Balance Sheet.  We recognize this deferred revenue into revenue on a straight-line basis over 120 months, which ends September 2019 and is the period that we expect GM to benefit under the 2009 Settlement and Commercial Agreement.  We recognized revenue of $8.0 million, in 2013, 2012 and 2011 related to this agreement.
	In 2008, we entered into an agreement with GM to provide financial assistance to support the transition of our United Automobile, Aerospace and Agricultural Implement Workers of America (UAW) represented legacy labor at our original U.S. locations upon the resolution of the strike called by the International UAW (2008 AAM - GM Agreement).  Pursuant to this agreement, GM provided us $115.0 million in 2008 and $60.0 million in 2009. In total, we recorded deferred revenue of $213.7 million as a result of the 2008 AAM - GM Agreement, which included $38.7 million related to the fair value of the liability GM assumed for postretirement healthcare and life insurance coverage provided to UAW represented transitioned associates with earned credited service from AAM that have or will retire under plans operated by GM. We recognized this deferred revenue into revenue on a straight-line basis over a 45 month period, which ended February 2012 and was consistent with the period that we expected GM to benefit from the payments provided to us under the 2008 AAM - GM Agreement. We recognized $9.5 million of revenue in 2012 and $57.0 million of revenue in 2011 related to the 2008 AAM - GM Agreement.
	As of December 31, 2013, the majority of the remaining deferred revenue primarily relates to customer payments to implement capacity programs, which is generally recognized into revenue over the life of these programs. We recognized $10.5 million, $13.1 million and $15.6 million of revenue for these programs in 2013, 2012 and 2011, respectively.
	BUYDOWN PROGRAM In 2008, an involuntary Buydown Program (BDP) was initiated for associates that did not elect to participate in the Special Separation Program and continued employment with AAM.  Under the BDP, we agreed to make three annual lump-sum payments to associates in connection with, among other things, a base wage decrease.
	We recorded $2.3 million and $15.0 million of expense in 2012 and 2011, respectively, for the amortization of this prepaid asset, which we amortized over the period that we estimated that AAM would benefit from these payments, which ended in February 2012.
	RESEARCH AND DEVELOPMENT (R&D) COSTS We expense R&D, as incurred, in selling, general and administrative expenses on our Consolidated Statement of Income. R&D spending was $103.4 million, net of engineering, design and development recoveries, $123.4 million and $113.6 million in 2013, 2012 and 2011, respectively.
	CASH AND CASH EQUIVALENTS Cash and cash equivalents include all cash balances and highly liquid investments in money market funds with maturities of 90 days or less at the time of purchase.
	ACCOUNTS RECEIVABLE The majority of our accounts receivable are due from original equipment manufacturers (OEMs) in the automotive industry and are past due when payment is not received within the stated terms. Trade accounts receivable for our largest customer, GM, are generally due within approximately 50 days from the date of receipt.
	Amounts due from customers are stated net of allowances for doubtful accounts. We determine our allowances by considering factors such as the length of time accounts are past due, our previous loss history, the customer's ability to pay its obligation to us, and the condition of the general economy and the industry as a whole. The allowance for doubtful accounts was $4.9 million and $6.5 million as of December 31, 2013 and 2012, respectively. We write-off accounts receivable when they become uncollectible.
	CUSTOMER TOOLING AND PRE-PRODUCTION COSTS RELATED TO LONG-TERM SUPPLY AGREEMENTS Engineering, R&D, and other pre-production design and development costs for products sold on long-term supply arrangements are expensed as incurred unless we have a contractual guarantee for reimbursement from the customer. Costs for tooling used to make products sold on long-term supply arrangements for which we have either title to the assets or the non-cancelable right to use the assets during the term of the supply arrangement are capitalized in property, plant and equipment. Capitalized items and customer receipts in excess of tooling costs specifically related to a supply arrangement are amortized over the shorter of the term of the arrangement or over the estimated useful lives of the related assets.
	INVENTORIES We state our inventories at the lower of cost or market.  The cost of our inventories is determined using the FIFO method.  When we determine that our gross inventories exceed usage requirements, or if inventories become obsolete or otherwise not saleable, we record a provision for such loss as a component of our inventory accounts.
	Inventories consist of the following:
		December 31,
		2013				2012
		(in millions)
	Raw materials and work-in-progress	$	263.4			$	220.3
	Finished goods	25.7				25
	Gross inventories	289.1				245.3
	Inventory valuation reserves	(27.3		)		(21.0		)
	Inventories, net	$	261.8			$	224.3
	PROPERTY, PLANT AND EQUIPMENT We state property, plant and equipment, including amortizable tooling, at historical cost, as adjusted for impairments. Construction in progress includes costs incurred for the construction of buildings and building improvements, and machinery and equipment in process. Repair and maintenance costs that do not extend the useful life or otherwise improve the utility of the asset beyond its existing useful state are expensed in the period incurred.
	We record depreciation and tooling amortization on the straight-line method over the estimated useful lives of the depreciable assets. Depreciation and tooling amortization amounted to $151.8 million, $130.9 million and $123.7 million in 2013, 2012 and 2011, respectively.
	Property, plant and equipment consists of the following:
		Estimated		December 31,
		Useful Lives		2013				2012
		(years)		(in millions)
	Land			$	29.5			$	27.8
	Land improvements	15-Oct		18.9				17.8
	Buildings and building improvements	15-40		306.6				293.3
	Machinery and equipment	3-12		1,648.60				1,512.60
	Construction in progress			95.1				123.1
				2,098.70				1,974.60
	Accumulated depreciation and amortization			(1,040.2		)		(964.9		)
	Property, plant and equipment, net			$	1,058.50			$	1,009.70
	IMPAIRMENT OF LONG-LIVED ASSETS When impairment indicators exist, we evaluate the carrying value of long-lived assets for potential impairment. We consider projected future undiscounted cash flows, trends and other circumstances in making such estimates and evaluations. If impairment is deemed to exist, the carrying amount of the asset is adjusted based on its fair value. Recoverability of assets “held for use” is determined by comparing the forecasted undiscounted cash flows of the operations to which the assets relate to their carrying amount. When the carrying value of an asset group exceeds its fair value and is therefore nonrecoverable, those assets are written down to fair value. Fair value is determined based on market prices, when available, or a discounted cash flow analysis performed using management estimates. See Note 2 - Restructuring Actions for detail on our 2012 asset impairment.
	GOODWILL We record goodwill when the purchase price of acquired businesses exceeds the value of their identifiable net tangible and intangible assets acquired. We periodically evaluate goodwill for impairment in accordance with the accounting guidance for goodwill and other indefinite-lived intangibles. We completed impairment tests in 2013 and 2012 and concluded that there was no impairment of our goodwill. The following table provides a reconciliation of changes in goodwill:
		December 31,
		2013				2012
		(in millions)
	Beginning balance	$	156.4			$	155.9
	Foreign currency translation	—				0.5
	Ending balance	$	156.4			$	156.4
	INTANGIBLE ASSETS We are currently in the process of developing and testing global enterprise resource planning (ERP) systems to upgrade many of our existing operating and financial systems. In connection with the development of these ERP systems, we recorded an intangible asset of $7.8 million in 2013 related to costs incurred to obtain software licenses from a third party, as well as costs to design and develop this internal-use software. This intangible asset is classified as other assets and deferred charges on our Consolidated Balance Sheet and will be amortized over the estimated useful life of our ERP systems. We recorded $0.1 million of expense for the amortization of this intangible asset in 2013.
	As part of the formation of e-AAM, we recorded intangible assets of $8.7 million in 2010, which represented the fair value of a GM license agreement for technology developed by Saab Automobile AB (Saab) when it was a subsidiary of GM, in-process research and development technology and a long-term supply agreement with Saab. In 2011, Saab, our former partner in the e-AAM joint venture, filed for bankruptcy and entered into liquidation status. As a result, in 2011, we recorded a $1.6 million impairment charge to selling, general and administrative expenses to write off the intangible asset associated with the long-term supply agreement with Saab. These intangible assets are classified as other assets and deferred charges on our Consolidated Balance Sheet and we expect to begin amortizing the assets on a straight-line basis over their estimated useful lives once development of the related technology is complete and we begin utilizing these assets.
	We recorded an intangible asset of $9.6 million as of December 31, 2008 which represents the fair value of the customer relationships acquired as part of an asset purchase agreement with FormTech Industries LLC. We recorded $1.9 million of expense for the amortization of this intangible asset in each of the years 2013, 2012 and 2011, and this intangible asset has been fully amortized as of December 31, 2013. This intangible asset was amortized on a straight-line basis over its estimated useful life of five years.
	DEBT ISSUANCE COSTS The costs related to the issuance or modification of long-term debt are deferred and amortized into interest expense over the life of each debt issue. As of December 31, 2013 and December 31, 2012, our unamortized debt issuance costs were $35.6 million and $33.0 million, respectively. Deferred amounts associated with the extinguishment of debt are expensed and classified as debt refinancing and redemption costs on our Consolidated Statement of Income.
	DERIVATIVES We recognize all derivatives on the balance sheet at fair value. If a derivative qualifies under the accounting guidance as a hedge, depending on the nature of the hedge, changes in the fair value of the derivative are either offset against the change in fair value of the hedged asset, liability or firm commitment through earnings or recognized in other comprehensive income until the hedged item is recognized in earnings. The ineffective portion of a derivative's change in fair value, and changes in the fair value of derivatives that do not qualify as hedges, are immediately recognized in earnings. See Note 4 - Derivatives and Risk Management, for more detail on our derivatives.
	CURRENCY TRANSLATION We translate the assets and liabilities of our foreign subsidiaries to U.S. dollars at end-of-period exchange rates. We translate the income statement elements of our foreign subsidiaries to U.S. dollars at average-period exchange rates. We report the effect of translation for our foreign subsidiaries that use the local currency as their functional currency as a separate component of stockholders' deficit. Gains and losses resulting from the remeasurement of assets and liabilities in a currency other than the functional currency of a subsidiary are reported in current period income. We also report any gains and losses arising from transactions denominated in a currency other than the functional currency of a subsidiary in current period income.
	USE OF ESTIMATES In order to prepare consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP), we are required to make estimates and assumptions that affect the reported amounts and disclosures in our consolidated financial statements. Actual results could differ from those estimates.
	EFFECT OF NEW ACCOUNTING STANDARDS On January 1, 2013, new accounting guidance regarding impairment testing of indefinite-lived intangible assets became effective. Under the new guidance, an entity testing an indefinite-lived intangible asset for impairment has the option of performing a qualitative impairment assessment before calculating the fair value of the asset. The adoption of this new accounting guidance did not have a significant effect on our impairment assessments of indefinite-lived intangible assets.
	On February 5, 2013, new accounting guidance was issued which requires entities to disclose additional information about items reclassified out of accumulated other comprehensive income (AOCI). The new guidance requires entities to disclose, either on the face of the financial statements or as a separate footnote to the financial statements, additional information regarding changes in AOCI balances by component, either before tax or net-of-tax, and requires entities to disclose significant items reclassified out of AOCI by component. The new guidance does not change the current accounting guidance which states that a total for comprehensive income must be reported in either a single continuous statement or two separate but consecutive statements. Other than additional disclosure requirements, the adoption of this new guidance has had no impact on our consolidated financial statements.
	On July 18, 2013, new accounting guidance was issued regarding financial statement presentation of an unrecognized tax benefit when a net operating loss (NOL) carryforward, a similar tax loss, or a tax credit carryforward exists. The new guidance requires entities to present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for an NOL carryforward, a similar tax loss, or a tax credit carryforward, except when one is not available as of the reporting date or the entity does not intend to use the deferred tax asset for this purpose. This guidance does not affect the tabular reconciliation of the total amounts of unrecognized tax benefits, as the tabular reconciliation presents the gross amount of unrecognized tax benefits. This new guidance will be effective for us as of January 1, 2015, with early adoption permitted. Other than a possible change in financial statement disclosure, we do not believe that the adoption of this new guidance will have a significant impact on our consolidated financial statements.

Restructuring_Actions

Restructuring Actions	12 Months Ended
	Dec. 31, 2013
Restructuring Actions [Abstract]	'
Restructuring, Impairment, and Other Activities Disclosure [Text Block]	'
	2	RESTRUCTURING ACTIONS
	In 2012, we incurred restructuring charges related to termination benefits and other ongoing restructuring actions.  In addition, in 2013, we continue to make payments related to charges incurred for restructuring actions taken in prior years. A summary of this activity for 2013 and 2012 is shown below:
		One-time Termination Benefits			Asset Impairment Charges			Asset Retirement Obligations			Other Restructuring Actions			Total
		(in millions)
	Accrual as of January 1, 2012	$	0.3		$	—		$	0.6		$	—		$	0.9
	Charges	1.7			5.8			—			23.2			30.7
	Cash utilization	(1.6		)	—			(0.1		)	(23.2		)	(24.9		)
	Non-cash utilization	—			(5.8		)	—			—			(5.8		)
	Accrual adjustments	(0.4		)	—			—			—			(0.4		)
	Accrual as of December 31, 2012	$	—		$	—		$	0.5		$	—		$	0.5
	Charges	—			—			—			—			—
	Cash utilization	—			—			(0.3		)	—			(0.3		)
	Non-cash utilization	—			—			—			—			—
	Accrual adjustments	—			—			—			—			—
	Accrual as of December 31, 2013	$	—		$	—		$	0.2		$	—		$	0.2
	ONE-TIME TERMINATION BENEFITS We expensed $1.7 million in 2012 primarily related to the continuation of healthcare for certain associates as a result of the Detroit Manufacturing Complex (DMC) and Cheektowaga Manufacturing Facility (CKMF) plant closures. We paid $1.6 million in 2012 related to one-time termination benefits which were initiated and expensed prior to 2011.
	We also recorded accrual adjustments in 2012 related to changes in previous estimates and currency translation adjustments.
	ASSET IMPAIRMENTS We recorded asset impairment charges of $5.8 million in 2012 associated with previously leased assets at DMC that we had elected to buyout in 2011, as we no longer had a use for these assets.
	ASSET RETIREMENT OBLIGATIONS We paid $0.3 million and $0.1 million related to our asset retirement obligations in 2013 and 2012, respectively.
	OTHER RESTRUCTURING ACTIONS We incurred charges related to the redeployment of assets to support capacity utilization initiatives and other related activities as a result of our DMC and CKMF plant closures. We expensed and paid $23.2 million in 2012 related to these actions.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2013
Long-term Debt, Unclassified [Abstract]	'
Long-term Debt [Text Block]	'
		LONG-TERM DEBT AND LEASE OBLIGATIONS
	Long-term debt consists of the following:
		December 31,
		2013		2012
		(in millions)
	Amended Revolving Facility	$	—	$	—
	Term Facility	150		—
	9.25% Notes, net of discount	—		337.5
	7.875% Notes	—		300
	7.75% Notes	200		200
	6.625% Notes	550		550
	6.25% Notes	400		—
	5.125% Notes	200		—
	Foreign credit facilities	53.8		61
	Capital lease obligations	5.3		5.6
	Long-term debt	$	1,559.10	$	1,454.10
	AMENDED REVOLVING FACILITY AND TERM FACILITY On September 13, 2013, we amended and restated the Credit Agreement dated as of January 9, 2004 (as amended and restated, the Amended and Restated Credit Agreement and the facility thereunder, the Amended Revolving Facility). As of December 31, 2013, the Amended Revolving Facility provided up to $523.5 million of revolving bank financing commitments through September 13, 2018. At December 31, 2013, $501.6 million was available under the Amended Revolving Credit Facility, which reflected a reduction of $21.9 million for standby letters of credit issued against the facility.
	The Amended and Restated Credit Agreement, among other things, increased the aggregate commitments by approximately $158.5 million and extended the maturity date from June 30, 2016 to September 13, 2018. In addition, the Amended and Restated Credit Agreement provides for a senior secured term loan A facility in an aggregate principal amount of $150.0 million (Term Facility). The full amount of the Term Facility was drawn in 2013 and remains outstanding as of December 31, 2013. We paid debt issuance costs of $6.9 million in 2013 associated with the execution of our Amended Revolving Facility and Term Facility. In 2012 and 2011, we paid debt issuance costs of $1.7 million and $5.9 million, respectively, associated with the amendments and restatements of our revolving credit facility.
	Borrowings under the Amended Revolving Facility and Term Facility bear interest at rates based on adjusted LIBOR or an alternate base rate, plus an applicable margin. The applicable margin for LIBOR-based loans will be between 1.5% and 3.0%.
	Under the Amended Revolving Facility, certain negative covenants were revised to provide increased flexibility. In the event AAM achieves investment grade corporate credit ratings from S&P and Moody's, AAM may elect to release all of the collateral from the liens granted pursuant to the collateral agreement, subject to notice requirements and other conditions. The Amended Revolving Facility and Term Facility are secured on a first priority basis by all or substantially all of the assets of AAM and each guarantor under the Collateral Agreement dated as of November 7, 2008, as amended and restated as of September 13, 2013.
	On March 20, 2013, we terminated our class C loan facility of $72.8 million, which would have matured on June 30, 2013. Upon termination, we expensed $0.5 million of unamortized debt issuance costs related to the class C facility. We had been amortizing the debt issuance costs over the expected life of the borrowing.
	The Amended Revolving Facility provides back-up liquidity for our foreign credit facilities. We intend to use the availability of long-term financing under the Amended Revolving Facility to refinance any current maturities related to such credit facilities that are not otherwise refinanced on a long-term basis in their local markets.
	9.25% NOTES In 2009, we issued $425.0 million of 9.25% senior secured notes due 2017 (9.25% Notes). The notes were issued at a discount of $5.5 million. Net proceeds from these notes were used for the repayment of certain indebtedness.
	In 2012 and 2011, we elected to exercise an option to redeem 10% of the original amount of our 9.25% Notes outstanding at a redemption price of 103% of the principal amount. This resulted in principal payments of $42.5 million and $1.3 million for the redemption premiums, as well as payments of accrued interest in both 2012 and 2011. We expensed $1.0 million in 2012 and $1.4 million in 2011 for the write-off of a proportional amount of unamortized debt discount and issuance costs related to this debt that we had been amortizing over the expected life of the borrowing.
	Pursuant to the terms of our 9.25% Notes, in the fourth quarter of 2013, we voluntarily redeemed the remaining outstanding 9.25% Notes using the proceeds from the Term Facility and the issuance of the 5.125% Notes. This resulted in a principal payment of $340.0 million and $18.9 million for redemption premiums, as well as payments of accrued interest. We expensed $6.7 million in 2013 related to the write-off of the remaining unamortized debt discount and issuance costs related to our 9.25% Notes that we had been amortizing over the expected life of the borrowing.
	7.875% NOTES In 2007, we issued $300.0 million of 7.875% senior unsecured notes due 2017 (7.875% Notes). Net proceeds from these notes were used for general corporate purposes, including payment of amounts outstanding under our revolving credit facility.
	On March 1, 2013, in connection with a cash tender offer, we purchased $172.6 million aggregate principal amount of the 7.875% Notes, and paid accrued interest. Upon purchase, we expensed $5.2 million related to a tender premium, $0.1 million of professional fees and unamortized debt issuance costs of $1.2 million related to this debt. We had been amortizing the debt issuance costs over the expected life of the borrowing.
	On March 15, 2013, we voluntarily redeemed the remaining 7.875% Notes outstanding. This resulted in a principal payment of $127.4 million, a payment of $3.3 million related to a redemption premium, as well as payment of accrued interest. Upon redemption, we expensed $0.9 million of unamortized debt issuance costs related to this debt. We had been amortizing the debt issuance costs over the expected life of the borrowing.
	7.75% NOTES In 2011, we issued $200.0 million of 7.75% senior unsecured notes due 2019 (7.75% Notes). Net proceeds from these notes were used for general corporate purposes, including the repayment of certain amounts outstanding under our revolving credit facility. In 2011, we paid debt issuance costs of $5.0 million related to the 7.75% Notes.
	6.625% NOTES In 2012, we issued $550.0 million of 6.625% senior unsecured notes due 2022 (6.625% Notes). Concurrent with the offering of the 6.625% Notes, we made a tender offer to purchase our 5.25% Notes, of which the aggregate principal amount then outstanding was $250.0 million. Net proceeds from the 6.625% Notes were used to fund the purchase of $137.8 million of the outstanding 5.25% Notes pursuant to the tender offer, certain pension obligations and for other general corporate purposes. We also used the net proceeds to fund the redemption of the remaining 5.25% Notes, including the payment of interest, and to redeem $42.5 million aggregate principal amount of our 9.25% Notes. We paid debt issuance costs of $8.9 million related to the 6.625% Notes in 2012.
	6.25% NOTES In the first quarter of 2013, we issued $400.0 million of 6.25% senior unsecured notes due 2021 (6.25% Notes). Concurrent with the offering of the 6.25% Notes, we made a tender offer to purchase our 7.875% Notes, of which the aggregate principal amount outstanding at the time of the tender offer was $300.0 million. Net proceeds from the 6.25% Notes were used to fund the purchase pursuant to the tender offer and the subsequent redemption of the remaining 7.875% Notes and for other general corporate purposes. We paid debt issuance costs of $6.6 million in 2013 related to the 6.25% Notes.
	5.125% NOTES In the fourth quarter of 2013, we issued $200.0 million of 5.125% senior unsecured notes due 2019 (5.125% Notes). Net proceeds from the 5.125% Notes were used to redeem the remaining $190.0 million outstanding under our 9.25% Notes. We paid debt issuance costs of $3.1 million in 2013 related to the 5.125% Notes.
	LEASES We lease certain facilities under capital leases expiring at various dates. The gross asset cost of our capital leases was $6.7 million at both December 31, 2013 and December 31, 2012. The net book value included in property, plant and equipment, net on the balance sheet was $5.3 million and $5.6 million at December 31, 2013 and 2012, respectively. The weighted-average interest rate on these capital lease obligations at December 31, 2013 was 8.9%.
	We also lease certain manufacturing machinery and equipment, commercial office and production facilities, vehicles and other assets under operating leases expiring at various dates. In 2013 and 2012, we entered into various sale-leaseback transactions for equipment to be used in production starting in 2013. We received proceeds of $24.1 million and $12.1 million in 2013 and 2012, respectively, as a result of these transactions. Future minimum payments under noncancelable operating leases are as follows: $19.6 million in 2014, $17.4 million in 2015, $15.5 million in 2016, $13.6 million in 2017 and $6.8 million in 2018. Our total expense relating to operating leases was $17.6 million, $9.0 million and $6.8 million in 2013, 2012 and 2011, respectively. This includes a reduction to cost of goods sold of $0.5 million related to the purchase of previously idled leased assets in 2011.
	FOREIGN CREDIT FACILITIES We utilize local currency credit facilities to finance the operations of certain foreign subsidiaries. These credit facilities, some of which are guaranteed by Holdings and/or AAM, Inc., expire at various dates through July 2019. At December 31, 2013, $53.8 million was outstanding under these facilities and an additional $56.7 million was available.
	DEBT MATURITIES Aggregate maturities of long-term debt are as follows (in millions):
	2014	$	36.8
	2015	21.1
	2016	17.2
	2017	19.1
	2018	109.2
	Thereafter	1,355.70
	Total	$	1,559.10
	INTEREST EXPENSE AND INVESTMENT INCOME Interest expense was $115.9 million in 2013, $101.6 million in 2012 and $83.9 million in 2011. The increases in interest expense in 2013 as compared to 2012, and 2012 as compared to 2011, reflect higher average outstanding borrowings year over year. We capitalized interest of $6.6 million in 2013, $8.2 million in 2012 and $8.3 million in 2011. The weighted-average interest rate of our long-term debt outstanding at December 31, 2013 was 6.3% as compared to 7.9% and 8.0% at December 31, 2012 and 2011, respectively. The amount of accrued interest included in other accrued expenses on our Consolidated Balance Sheet was $19.9 million and $35.1 million as of December 31, 2013 and 2012, respectively.
	Investment income was $0.6 million in both 2013 and 2012 and $1.2 million in 2011. Investment income includes interest and dividends earned on cash and cash equivalents and realized and unrealized gains and losses on our short-term investments during the period.

Derivatives

Derivatives	12 Months Ended
	Dec. 31, 2013
Derivatives [Abstract]	'
Derivative Instruments and Hedging Activities Disclosure [Text Block]	'
		DERIVATIVES AND RISK MANAGEMENT
	DERIVATIVE FINANCIAL INSTRUMENTS In the normal course of business, we are exposed to market risk associated with changes in foreign currency exchange rates and interest rates. To manage a portion of these inherent risks, we may purchase certain types of derivative financial instruments based on management's judgment of the trade-off between risk, opportunity and cost. We do not hold or issue derivative financial instruments for trading or speculative purposes. The ineffective portion of any hedge is included in current earnings. The impact of hedge ineffectiveness was not significant in any of the periods presented.
	CURRENCY FORWARD CONTRACTS From time to time, we use foreign currency forward contracts to reduce the effects of fluctuations in exchange rates, primarily relating to the Mexican Peso, Euro, Swedish Krona, Polish Zloty and Pound Sterling. We had forward contracts with a notional amount of $67.2 million and $31.9 million outstanding at December 31, 2013 and 2012, respectively.
	The following table summarizes the reclassification of pre-tax derivative gains (losses) into net income from accumulated other comprehensive income (loss):
		Location of Gain (Loss) Reclassified into Net Income	Gain (loss) Reclassified During the Twelve Months Ended December 31,					Gain Expected to be Reclassified During the Next 12 Months
			2013		2012
			(in millions)
	Currency forward contracts	Cost of Goods Sold	$	2.8	$	(1.8	)	$	0.3
	CONCENTRATIONS OF CREDIT RISK In the normal course of business, we provide credit to customers. We periodically evaluate the creditworthiness of our customers and we maintain reserves for potential credit losses.
	Sales to GM were approximately 71% of our consolidated net sales in 2013 and 73% of our total consolidated net sales in both 2012 and 2011. Accounts and other receivables due from GM were $278.5 million at year-end 2013 and $325.8 million at year-end 2012. Sales to Chrysler Group LLC (Chrysler) were approximately 12% of our consolidated net sales in 2013, 10% in 2012 and 8% in 2011. Accounts receivable due from Chrysler were $85.9 million at year-end 2013 and $43.5 million at year-end 2012. No other single customer accounted for more than 10% of our consolidated net sales in any year presented.
	In addition, our total GM postretirement cost sharing asset was $255.9 million as of December 31, 2013 and $273.0 million as of December 31, 2012. See Note 6 - Employee Benefit Plans for more detail on this cost sharing asset.
	We diversify the concentration of invested cash and cash equivalents among different financial institutions and we monitor the selection of counterparties to other financial instruments to avoid unnecessary concentrations of credit risk.

Fair_Value

Fair Value	12 Months Ended
	Dec. 31, 2013
Fair Value [Abstract]	'
Fair Value Disclosures [Text Block]	'
		FAIR VALUE
	The fair value accounting guidance defines fair value as “the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.”  The definition is based on an exit price rather than an entry price, regardless of whether the entity plans to hold or sell the asset.  This guidance also establishes a fair value hierarchy to prioritize inputs used in measuring fair value as follows:
	•	Level 1:  Observable inputs such as quoted prices in active markets;
	•	Level 2:  Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and
	•	Level 3:  Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.
	FINANCIAL INSTRUMENTS  The estimated fair values of our financial assets and liabilities that are recognized at fair value on a recurring basis, using available market information and other observable data are as follows:
		December 31, 2013						December 31, 2012
		Carrying Amount			Fair Value			Carrying Amount			Fair Value			Input
		(in millions)						(in millions)
	Balance Sheet Classification
	Cash equivalents	$	6.1		$	6.1		$	6.5		$	6.5		Level 1
	Prepaid expenses and other
	Currency forward contracts	0.7			0.7			2.3			2.3			Level 2
	Other accrued expenses
	Currency forward contracts	0.4			0.4			—			—			Level 2
	The carrying values of our cash, accounts receivable, accounts payable and accrued liabilities approximate their fair values due to the short-term maturities of these instruments.  The carrying values of our borrowings under the foreign credit facilities approximate their fair values due to the frequent resetting of the interest rates.  We estimated the fair value of our outstanding debt using available market information and other observable data to be as follows:
		December 31, 2013						December 31, 2012
		Carrying Amount			Fair Value			Carrying Amount			Fair Value			Input
		(in millions)						(in millions)
	Amended Revolving Facility	$	—		$	—		$	—		$	—		Level 2
	Term Facility	150			147.8			—			—			Level 2
	9.25% Notes	—			—			337.5			377.4			Level 2
	7.875% Notes	—			—			300			310.1			Level 2
	7.75% Notes	200			227.5			200			216.5			Level 2
	6.625% Notes	550			578.9			550			555.5			Level 2
	6.25% Notes	400			423			—			—			Level 2
	5.125% Notes	200			206			—			—			Level 2
	Investments in our defined benefit pension plans are stated at fair value. See Note 6 - Employee Benefit Plans for additional fair value disclosures of our pension plan assets.
	LONG-LIVED ASSETS  In 2012 and 2011, as part of our impairment analysis, we were required to measure the fair value of certain long-lived assets.  In 2012, we considered the expected future use of certain long-lived assets remaining at our Detroit Manufacturing Complex. In 2011, we considered the expected future use of the long-lived assets located at our Cheektowaga Manufacturing Facility. Assets that were not to be redeployed to other AAM facilities were determined to be fully impaired.
	The following table summarizes impairments of long-lived assets measured at fair value on a nonrecurring basis subsequent to initial recognition:
	Balance Sheet Classification		Fair Value Measurements using Level 3 Inputs			Asset Impairment Recorded in Twelve Months ended December 31, 2012			Fair Value Measurements using Level 3 Inputs			Asset Impairment Recorded in Twelve Months ended December 31, 2011
			(in millions)
	Property, plant and equipment, net		$	—		$	5.8		$	—		$	8.1
	Other assets and deferred charges		—			—			—			0.5
	In 2012, we reassessed the expected future use of certain assets remaining at DMC that were previously leased assets that had been purchased in 2011 for $18.6 million. As a result, we recorded an impairment charge of $5.8 million related to the assets that we no longer intended to redeploy and use at another AAM facility. In 2011, at the time we elected to buyout the leases, we considered the expected future use of these long-lived assets as part of our fair value measurement and recorded them at their estimated fair value. Assets that were not to be redeployed to other AAM facilities were written down to their estimated net realizable value, which resulted in a net charge to cost of goods sold of $5.3 million in 2011.
	Finite-lived Intangibles In 2011, Saab, our former partner in the e-AAM joint venture, filed for bankruptcy and entered into liquidation status. As a result, in 2011, we recorded a $1.6 million impairment charge to selling, general and administrative expenses to write off the intangible asset associated with the long-term supply agreement with Saab acquired as part of our joint venture formation in 2010. The following table summarizes the impairment of finite-lived intangible assets measured at fair value on a nonrecurring basis subsequent to initial recognition:
	Balance Sheet Classification		Fair Value Measurement Using Level 3 Inputs			Impairment Recorded in the Twelve Months Ended December 31, 2011
			(in millions)
	Other assets and deferred charges		$	—		$	1.6

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2013
Employee Benefit Plans [Abstract]	'
Compensation and Employee Benefit Plans [Text Block]	'
	6. EMPLOYEE BENEFIT PLANS
	PENSION AND OTHER POSTRETIREMENT DEFINED BENEFIT PLANS We sponsor various qualified and non-qualified defined benefit pension plans for our eligible associates. We also maintain hourly and salaried benefit plans that provide postretirement medical, dental, vision, legal and life insurance benefits (OPEB) to our eligible retirees and their dependents in the U.S.
	AAM and GM share proportionally in the cost of OPEB for eligible retirees based on the length of service an employee had with AAM and GM.  We have included in our OPEB obligation the amounts expected to be received pursuant to this agreement of $255.9 million and $273.0 million at December 31, 2013 and December 31, 2012, respectively. We have also recorded a corresponding asset for these amounts on our Consolidated Balance Sheet, $13.9 million that is classified as a current asset and $242.0 million that is classified as a noncurrent asset as of December 31, 2013.
	Actuarial valuations of our benefit plans were made as of December 31, 2013 and 2012. The principal weighted-average assumptions used in the year-end valuation of our U.S. and U.K. plans appear in the following table. The U.S. discount rates are based on an actuarial review of a hypothetical portfolio of long-term, high quality corporate bonds matched against the expected payment stream for each of our plans. The U.K. discount rate is based on a review of long-term bonds, in consideration of the average duration of plan liabilities. The assumptions for expected return on plan assets are based on future capital market expectations for the asset classes represented within our portfolios and a review of long-term historical returns. The rates of increase in compensation and health care costs are based on current market conditions, inflationary expectations and historical information.
		Pension Benefits																		OPEB
		2013						2012						2011						2013			2012		2011
		U.S.			U.K			U.S.			U.K			U.S.			U.K.
	Discount rate	5	%		4.5	%		4.1	%		4.3	%		5.1	%		4.65	%		4.95	%		4.05	%	5.1	%
	Expected return on plan assets	7.5	%		5.15	%		7.5	%		4.35	%		8	%		4.6	%		N/A			N/A		N/A
	Rate of compensation increase	4	%		3.6	%		4	%		3.15	%		4	%		3.25	%		4	%		4	%	4	%
	The accumulated benefit obligation for all defined benefit pension plans was $744.5 million and $828.4 million at December 31, 2013 and December 31, 2012, respectively. As of December 31, 2013, the accumulated benefit obligation for our underfunded defined benefit pension plans was $612.6 million, the projected benefit obligation was $621.3 million and the fair value of assets for these plans was $570.1 million. The following table summarizes the changes in projected benefit obligations and plan assets and reconciles the funded status of the benefit plans, which is the net benefit plan liability:
		Pension Benefits								OPEB
		December 31,								December 31,
		2013				2012				2013				2012
		(in millions)								(in millions)
	Change in benefit obligation
	Benefit obligation at beginning of year	$	842.8			$	716.7			$	601.3			$	588.4
	Service cost	3.4				3.1				0.4				0.4
	Interest cost	33.8				35.1				13.2				15.1
	Plan amendments	—				6.1				(8.1		)		—
	Actuarial loss (gain)	(92.6		)		97.3				(0.7		)		(7.1		)
	Change in GM portion of OPEB obligation	—				—				(17.0		)		2.4
	Participant contributions	0.4				0.5				—				—
	Special and contractual termination benefits	—				12.8				—				18.3
	Settlements	—				—				—				(4.7		)
	Benefit payments	(35.3		)		(34.2		)		(11.2		)		(11.5		)
	Currency fluctuations	2.9				5.4				—				—
	Net change	(87.4		)		126.1				(23.4		)		12.9
	Benefit obligation at end of year	$	755.4			$	842.8			$	577.9			$	601.3
	Change in plan assets
	Fair value of plan assets at beginning of year	$	695.4			$	441.7			$	—			$	—
	Actual return on plan assets	49.2				57.3				—				—
	Employer contributions	0.8				225.4				11.2				11.5
	Participant contributions	0.4				0.5				—				—
	Benefit payments	(35.3		)		(34.2		)		(11.2		)		(11.5		)
	Currency fluctuations	2.9				4.7				—				—
	Net change	18				253.7				—				—
	Fair value of plan assets at end of year	$	713.4			$	695.4			$	—			$	—
	Amounts recognized in our balance sheets are as follows:
		Pension Benefits								OPEB
		December 31,								December 31,
		2013				2012				2013				2012
		(in millions)								(in millions)
	Noncurrent assets	$	9.3			$	11.8			$	—			$	—
	Current liabilities	(2.3		)		(1.3		)		(30.8		)		(28.6		)
	Noncurrent liabilities	(49.0		)		(157.9		)		(547.1		)		(572.7		)
	Net liability	$	(42.0	)		$	(147.4	)		$	(577.9	)		$	(601.3	)
	Pre-tax amounts recorded in accumulated other comprehensive income (AOCI), not yet recognized in net periodic benefit cost as of December 31, 2013 and 2012, consists of:
		Pension Benefits								OPEB
		December 31,								December 31,
		2013				2012				2013				2012
		(in millions)								(in millions)
	Net actuarial gain (loss)	$	(194.3	)		$	(298.6	)		$	4.9			$	3.3
	Net prior service credit (cost)	0.8				(4.7		)		18.1				11.8
	Total amounts recorded	$	(193.5	)		$	(303.3	)		$	23			$	15.1
	The components of net periodic benefit cost are as follows:
		Pension Benefits												OPEB
		2013				2012				2011				2013				2012				2011
		(in millions)												(in millions)
	Service cost	$	3.4			$	3.1			$	4.8			$	0.4			$	0.4			$	0.9
	Interest cost	33.8				35.1				37.1				13.2				15.1				17.1
	Expected asset return	(45.8		)		(34.7		)		(31.9		)		—				—				—
	Amortized actuarial loss	8.9				7.8				4.5				0.9				0.6				0.4
Amortized prior service cost (credit)	5.4				0.5				(0.1		)		(1.8		)		(2.0		)		(3.2		)
Special and contractual
termination benefits	—				12.8				—				—				16.2				—
Curtailment gain	—				—				—				—				(21.8		)		—
Settlement	—				—				0.1				—				(5.2		)		—
Net periodic benefit cost	$	5.7			$	24.6			$	14.5			$	12.7			$	3.3			$	15.2
Our postretirement cost sharing asset from GM is measured on the same basis as the portion of the obligation to which it relates. The actuarial gains and losses related to the GM portion of the OPEB obligation are recognized immediately in the Consolidated Statement of Income as an offset against the gains and losses related to the change in the corresponding GM postretirement cost sharing asset. These items are presented net in the change in benefit obligation and net periodic benefit cost components disclosed above. Remaining actuarial gains and losses are deferred and amortized over the expected future service periods of the active participants.
The estimated net actuarial loss and prior service credit for the defined benefit pension plans that is expected to be amortized from AOCI into net periodic benefit cost in 2014 are $5.5 million and $0.1 million, respectively. The estimated net actuarial loss and prior service credit for the other defined benefit postretirement plans that is expected to be amortized from AOCI into net periodic benefit cost in 2014 are $0.5 million and $2.7 million, respectively.
For measurement purposes, a weighted average annual increase in the per-capita cost of covered health care benefits of 7.5% was assumed for 2014. The rate was assumed to decrease gradually to 5.0% by 2019 and to remain at that level thereafter. Health care cost trend rates have a significant effect on the amounts reported for the health care plans. A 1.0% increase in the assumed health care cost trend rate would have increased total service and interest cost in 2013 and the postretirement obligation, net of GM cost sharing, at December 31, 2013 by $1.6 million and $33.6 million, respectively. A 1.0% decrease in the assumed health care cost trend rate would have decreased total service and interest cost in 2013 and the postretirement obligation, net of GM cost sharing, at December 31, 2013 by $1.4 million and $28.1 million, respectively.
The expected future pension and other postretirement benefits to be paid, net of GM cost sharing, for each of the next five years and in the aggregate for the succeeding five years thereafter are as follows: $55.9 million in 2014; $57.3 million in 2015; $57.8 million in 2016; $59.0 million in 2017; $59.4 million in 2018 and $309.2 million for 2019 through 2023. These amounts were estimated using the same assumptions that were used to measure our 2013 year-end pension and OPEB obligations and include an estimate of future employee service.
Contributions In 2012, AAM and the Pension Benefit Guaranty Corporation entered into an agreement regarding any liability that may have arisen under the Employee Retirement Income Security Act of 1974 in connection with the closures of DMC and CKMF. As part of this agreement, in 2012, we contributed $114.7 million in excess of our statutory minimum to our U.S. hourly pension plan.
Due to our significant pension contributions made in 2012, we do not expect to make any cash payments in 2014 to satisfy our regulatory funding requirements. We expect our cash outlay, net of GM cost sharing, for OPEB to be approximately $17 million in 2014.
Labor relations In 2012, we recorded a gain of $21.8 million in cost of goods sold for the curtailment of certain other postretirement benefits (OPEB). This resulted primarily from the reduction in expected future OPEB related to the DMC and CKMF hourly associates who have terminated employment from AAM as a result of our plant closures. These curtailment gains resulted in an increase in our accumulated other comprehensive loss of $21.8 million pre-tax.
Also in 2012, we notified hourly associates of the termination of a benefit plan, which provided legal services to certain eligible hourly associates represented by the International UAW. As a result of terminating this plan, we recorded a settlement gain of $5.2 million in cost of goods sold in 2012. Recognition of this settlement gain reduced postretirement benefits and other long-term liabilities by $4.7 million and also reduced our accumulated other comprehensive loss by $0.5 million pre-tax.
Amendments to pension and OPEB plans and contractual termination benefits In the third quarter of 2013, we remeasured our AAM Supplemental Executive Retirement Plan (SERP) due to the passing of our Co-Founder and former Executive Chairman of the Board of Directors. As a result of this remeasurement, we recorded $4.7 million in selling, general and administrative expense related to the acceleration of prior service cost. This SERP remeasurement also resulted in a decrease in postretirement benefits and other long-term liabilities of $16.4 million and a decrease in our accumulated other comprehensive loss of $13.7 million on our Consolidated Balance Sheet.
Effective August 1, 2012, we amended our AAM Supplemental Executive Retirement Plan to include an actuarial increase provision for participants that work past the age of 65, among other things. As a result of these plan amendments, we increased our pension liability by $6.1 million in 2012. This adjustment was recorded to AOCI and has been fully amortized in 2013, due to the passing of our co-Founder and former Executive Chairman of the Board of Directors.
As a result of our election to apply the provisions of Moving Ahead for Progress in the 21st Century Act (MAP-21), in addition to certain actions we took in 2012, we agreed to provide pension and postretirement benefits to certain eligible UAW associates whose employment had been terminated in connection with the DMC and CKMF plant closures. In 2012, we recorded $28.7 million in cost of goods sold, for these pension and postretirement benefits. These incremental pension and postretirement benefits were also agreed to in connection with the lawsuit filed by the International UAW against AAM. See Note 10 - Commitments and Contingencies for more detail on this lawsuit.
Pension plan assets The weighted-average asset allocations of our pension plan assets at December 31, 2013 and 2012 appear in the following table. The asset allocation for our plans is developed in consideration of the demographics of the plan participants and expected payment stream of the benefit obligation.
	U.S.								U.K.
							Target								Target
	2013			2012			Allocation		2013			2012			Allocation
Equity securities	42.5	%		38.3	%		30% - 65%		30.7	%		34.8	%		25% - 35%
Fixed income securities	48.5			52.3			35% - 55%		59			55.1			55% - 65%
Hedge funds	8.8			8.5			0% - 15%		10.2			—			5% - 15%
Cash	0.2			0.9			0% - 5%		0.1			10.1			0% - 10%
Total	100	%		100	%				100	%		100	%
The primary objective of our pension plan assets is to provide a source of retirement income for participants and beneficiaries. Our primary financial objectives for the pension plan assets have been established in conjunction with a comprehensive review of our current and projected financial requirements. These objectives include having the ability to pay all future benefits and expenses when due, maintaining flexibility and minimizing volatility. These objectives are based on a long-term investment horizon.
Postretirement Benefit Plan Assets Investments in our defined benefit plans are stated at fair value. Level 1 assets are valued using quoted market prices that represent the asset value of the shares held by the trusts. The level 2 assets are investments in pooled funds, which are valued using a model to reflect the valuation of their underlying assets that are publicly traded with observable values. The fair value of our level 3 postretirement benefit plan assets are measured by compiling the portfolio holdings and independently valuing the securities in those portfolios. The fair values of our pension plan assets are as follows:
December 31, 2013
Asset Categories		Level 1				Level 2				Level 3				Total
		(in millions)
Cash & Cash Equivalents		$	1.5			$	—			$	—			$	1.5
Equity
U.S. Large Cap		128				—				—				128
U.S. Small/Mid Cap		49.4				—				—				49.4
World Equity		109.3				—				—				109.3
Fixed Income Securities
Government & Agencies		70.5				63				—				133.5
Corporate Bonds - Investment Grade		167.1				—				—				167.1
Corporate Bonds - Non-investment Grade		25.8				—				—				25.8
Emerging Market Debt		17.4				—				—				17.4
Other		16.9				—				—				16.9
Hedge Funds
Property Funds		—				—				7.1				7.1
Multi Strategy Hedge Fund		—				—				57.4				57.4
Total Plan Assets		$	585.9			$	63			$	64.5			$	713.4
December 31, 2012
Asset Categories		Level 1				Level 2				Level 3				Total
		(in millions)
Cash & Cash Equivalents		$	18.5			$	—			$	—			$	18.5
Equity
U.S. Large Cap		104				—				—				104
U.S. Small/Mid Cap		46.9				—				—				46.9
World Equity		111.2				—				—				111.2
Fixed Income Securities
Government & Agencies		100.4				—				—				100.4
Corporate Bonds - Investment Grade		204.9				—				—				204.9
Corporate Bonds - Non-investment Grade		26.4				—				—				26.4
Emerging Market Debt		20.5				—				—				20.5
Other		15				—				—				15
Hedge Funds
Multi Strategy Hedge Fund		—				—				47.6				47.6
Total Plan Assets		$	647.8			$	—			$	47.6			$	695.4
The changes in the fair value of our level 3 assets in the Property Funds and Multi Strategy Hedge Fund are as follows:
	December 31,
	2013				2012
	(in millions)
Beginning balance	$	47.6			$	46.5
Actual return on plan assets:
Relating to assets still held at the reporting date	3.5				1.1
Purchases, sales and settlements, net	13.4				—
Ending balance	$	64.5			$	47.6
DEFINED CONTRIBUTION PLANS Most of our salaried U.S. associates are eligible to participate in voluntary savings plans. Our maximum match is 50% of eligible salaried associates' contribution up to 10% of their eligible salary. Matching contributions amounted to $3.9 million in 2013, $3.3 million in 2012 and $3.2 million in 2011. U.S. salaried associates are eligible to receive an additional annual retirement contribution (ARC) benefit between 3% to 5% of eligible salary, depending on years of service. We made ARC contributions of $4.6 million, $4.4 million and $3.6 million in 2013, 2012 and 2011, respectively.
As part of the 2008 labor agreements, certain UAW represented associates at our original U.S. locations became eligible for a Company match on associate contributions made to the voluntary savings plans, which began in 2009. Our maximum match will be 25% of hourly associates' contribution up to the first 6% of their contributions. Matching contributions amounted to $0.1 million in both 2013 and 2012, and $0.2 million in 2011. Certain UAW represented associates are also eligible to receive an ARC benefit of 5% of eligible wages, which also began in 2009. We made ARC contributions of $1.9 million in 2013, $1.6 million in 2012 and $1.9 million in 2011 related to these associates.
DEFERRED COMPENSATION PLAN Certain U.S. associates are eligible to participate in a non-qualified deferred compensation plan. Payments of $6.1 million, $0.8 million and $1.1 million have been made in 2013, 2012 and 2011, respectively, to eligible associates that have elected distributions. Included in these payments, in 2013, was a distribution of $5.6 million to the beneficiary of the plan upon the passing of our Co-Founder and former Executive Chairman of the Board of Directors. This payment resulted in a $5.6 million reduction in postretirement benefits and other long-term liabilities on our Consolidated Balance Sheet and was partially offset by proceeds of $5.0 million, which AAM received as the beneficiary of a key man life insurance policy.
At December 31, 2013 and 2012, our deferred compensation liability was $6.2 million and $11.3 million, respectively. Due to the changes in the value of this deferred compensation plan we increased our liability by $0.8 million, $1.3 million and $0.3 million in 2013, 2012 and 2011, respectively.

Stock_Based_Compensation

Stock Based Compensation	12 Months Ended
	Dec. 31, 2013
Stock-based Compensation [Abstract]	'
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]	'
	STOCK-BASED COMPENSATION
	At December 31, 2013, we had grants outstanding under stock incentive compensation plans approved by our stockholders. Under these plans, a total of 18.5 million shares have been authorized for issuance to our directors, officers and certain other associates in the form of options, unvested restricted stock or other awards that are based on the value of our common stock. Shares available for future grants at December 31, 2013 were 2.9 million. The current stock plan will expire in April 2022.
	STOCK OPTIONS Under the terms of the plans, stock options are granted at the market price of the stock on the grant date. The contractual term of outstanding stock options is 10 years. We issue new shares to satisfy stock-based awards.
	Stock option awards become exercisable in three approximately equal annual installments beginning one year from the date of grant.
	The following table summarizes activity relating to our stock options:
					Weighted-
		Number of			Average Exercise
		Shares			Price Per Share
		(in millions, except per share data)
	Outstanding at January 1, 2011	5			$	25.01
	Options granted	—			—
	Options exercised	(0.5	)		8.69
	Options canceled	(0.6	)		26.96
	Outstanding at December 31, 2011	3.9			$	26.95
	Options granted	0.2			9.19
	Options exercised	(0.1	)		2.81
	Options canceled	(1.0	)		25.12
	Outstanding at December 31, 2012	3			$	27.08
	Options granted	—			—
	Options exercised	(0.1	)		10.59
	Options canceled	(0.9	)		24.28
	Outstanding at December 31, 2013	2			$	29.22
	Exercisable at December 31, 2011	3.8			$	27.25
	Exercisable at December 31, 2012	2.8			$	28.02
	Exercisable at December 31, 2013	2			$	29.22
	As of December 31, 2013, there were no unvested stock options. The total intrinsic value of options outstanding and exercisable as of December 31, 2013 was $3.2 million. The total intrinsic value of stock options exercised was $0.8 million in 2013, $0.5 million in 2012 and $3.0 million in 2011.
	The following is a summary of the range of exercise prices for stock options that are outstanding and exercisable at December 31, 2013:
						Weighted-				Weighted-
	Range of		Stock Options			Average Exercise		Weighted-Average	Stock Options	Average Exercise
	Exercise Prices		Outstanding			Price Per Share		Contractual Life	Exercisable	Price Per Share
			(in millions, except per share data)					(in years)	(in millions, except per share data)
	$9.19 - $15.58		0.4			$	13.35	3.9	0.4	$	13.35
	$19.54 - $26.65		0.6			26.07		2.3	0.6	26.07
	$33.71 - $40.83		1			38.53		0.1	1	38.53
			2			$	29.22	1.6	2	$	29.22
	We estimated the fair value of our employee stock options on the date of grant using the Black-Scholes option-pricing model with the following assumptions:
		2012
	Expected volatility	47		%
	Risk-free interest rate	1.17		%
	Dividend yield	—		%
	Expected life of options	6 years
	Weighted-average grant-date fair value	$	4.18
	Expected volatility was based on the daily changes in our historical common stock prices over a period equal to the expected life of the award. The risk-free rate is based on the U.S. Treasury yield curve in effect at the time of the grant corresponding to the expected life of the options. Our dividend yield is based on the dividend at the time of grant. The expected life of options is based on historical stock option exercise patterns and the terms of the options.
	OTHER STOCK-BASED COMPENSATION We awarded performance accelerated restricted stock, restricted stock and restricted stock units (PARS, RS and RSUs, respectively). The total amount of compensation expense associated with the RSUs settled in cash is recorded as an accrued liability when incurred while the total amount of compensation expense associated with PARS, RS and RSUs settled in stock is recorded to paid-in-capital. The PARS and RSUs vest over three years contingent upon the satisfaction of future financial performance targets specified by the plan and the RS vests over three years. The unearned compensation is expensed over the expected vesting period.
	The following table summarizes activity relating to our PARS, RS and RSUs:
					Weighted Average
		Number of			Grant Date Fair
		Shares/Units			Value per Share/Unit
		(in millions, except per share data)
	Outstanding at January 1, 2011	2.8			$	13.48
	Granted	—			—
	Vested	(1.1	)		17.41
	Canceled	(0.1	)		10.68
	Outstanding at December 31, 2011	1.6			$	10.74
	Granted	1			10.31
	Vested	(1.4	)		10.19
	Canceled	(0.1	)		26.02
	Outstanding at December 31, 2012	1.1			$	11.08
	Granted	0.9			12.79
	Vested	(0.7	)		11.06
	Canceled	—			—
	Outstanding at December 31, 2013	1.3			$	12.24
	As of December 31, 2013, unrecognized compensation cost related to unvested RSUs totaled $8.0 million. The weighted average period over which this cost is expected to be recognized is approximately two years. In 2013 and 2012, the total fair market value of PARS, RS and RSUs vested was $13.8 million and $17.6 million, respectively.
We made cash payments of $0.2 million and $0.4 million related to vested RSUs in 2012 and 2011, respectively.
PERFORMANCE AWARDS As of December 31, 2013, we have performance awards outstanding under our AAM 2009 long-term incentive plan, as well as our 2012 Omnibus Incentive Plan. We granted performance awards payable in cash to our officers and executives which vest in full over a three year performance period. The payout of these awards is based on a total shareholder return (TSR) measure that compares our TSR over the three-year performance period relative to the TSR of our pre-defined competitor peer group. Share price appreciation and dividends paid is measured over the performance period to determine TSR.
According to the applicable accounting guidance, these awards are considered to be stock-based compensation because the final payout amount is based “at least in part” on the price of our shares. As these awards are settled in cash, they are determined to be liability awards and will be remeasured at the end of each reporting period until settlement. The fair value of the performance awards is calculated on a quarterly basis using the Monte Carlo simulation approach and the liability is adjusted accordingly based on changes to the fair value and the percentage of time vested. The Monte Carlo simulation approach utilizes inputs on volatility assumptions, risk free rates, the price of the Company’s and our competitor peer group's common stock and their correlation as of each valuation date. Volatility assumptions are based on historical and implied volatility measurements.
We recognized compensation expense associated with the performance awards of approximately $7.9 million in 2013, $3.0 million in 2012 and $3.5 million in 2011. We have a liability of $10.8 million recorded as of December 31, 2013. Based on the current fair value, the estimated unrecognized compensation cost related to the performance awards totaled $1.2 million, as of December 31, 2013. The weighted average period over which this cost is expected to be recognized is twelve months.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Taxes [Abstract]	'
Income Tax Disclosure [Text Block]	'
	INCOME TAXES
	Income before income taxes for U.S. and non-U.S. operations was as follows:
		2013				2012				2011
		(in millions)
	U.S. income (loss)	$	(23.8	)		$	(6.0	)		$	20.3
	Non - U.S. income	110.1				37.5				117.8
	Total income before income taxes	$	86.3			$	31.5			$	138.1
	The following is a summary of the components of our provisions for income taxes:
		2013				2012				2011
		(in millions)
	Current
	Federal	$	(1.3	)		$	(3.3	)		$	(24.7	)
	Other state and local	0.1				1.1				(0.2		)
	Foreign	12.1				10.2				9.9
	Total current	$	10.9			$	8			$	(15.0	)
	Deferred
	Federal	$	(9.3	)		$	(347.1	)		$	22.3
	Other state and local	—				—				(1.4		)
	Foreign	(9.8		)		3.9				(4.9		)
	Total deferred	(19.1		)		(343.2		)		16
	Total income tax expense (benefit)	$	(8.2	)		$	(335.2	)		$	1
	The following is a reconciliation of our provision for income taxes to the expected amounts using statutory rates:
		2013			2012			2011
	Federal statutory	35	%		35	%		35	%
	Foreign income taxes	(48.5	)		(85.0	)		(34.6	)
	Change in enacted tax rate	(9.9	)		—			—
	State and local	0.2			3.5			(1.2	)
	Valuation allowance	12.4			(985.0	)		(30.7	)
	U.S. tax on unremitted foreign earnings	(0.2	)		(29.5	)		26.3
	Other	1.5			(3.2	)		5.9
	Effective income tax rate	(9.5	)%		(1,064.2	)%		0.7	%
	Our income tax expense and effective tax rate for 2013 primarily reflect favorable foreign tax rates, along with our inability to realize a tax benefit for current foreign losses. In the fourth quarter of 2013, new Mexican tax reform was enacted that, among other things, increased the tax rate related to Maquiladora Companies from 17.5% to 30%. We recorded a tax benefit of $8.5 million as a result of revaluing our deferred tax assets at the newly enacted rate.
	In 2013, we recorded tax expense of $4.8 million relating to changes in estimates in the U.S. and certain foreign jurisdictions. Our income tax benefit and effective tax rate for 2013 also reflects the impact of recording a tax benefit of $1.5 million relating to the release of a prior year unrecognized tax benefit due to the expiration of the applicable statute of limitations and a tax benefit of $3.3 million relating to an election we made in 2013 regarding the treatment of foreign exchange gains and losses in a foreign jurisdiction. During 2013, we also settled various income tax audits resulting in a reduction of our liability for unrecognized income tax benefits of $8.4 million and a cash payment of $4.7 million.
	In 2012, our business returned to a position of cumulative profitability on a pre-tax basis, considering our operating results for the three years ended December 31, 2012. We concluded that this record of cumulative profitability in recent years, in addition to the restructuring of our U.S. operations and our long range forecast showing continued profitability, provided sufficient positive evidence that our net U.S. federal tax benefits more likely than not would be realized. Accordingly, in 2012, we released the valuation allowance against our net federal deferred assets for entities in the U.S., resulting in a $337.5 million benefit in our 2012 provision for income taxes. Our income tax benefit and effective tax rate in 2012 reflect the impact of this valuation allowance reversal.
	Our income tax expense and effective tax rate for 2012 also reflect a net tax expense of $1.3 million related to the amendment of state income tax returns as a result of the settlement of federal income tax audits for the tax years 2004 through 2007.
	Our income tax expense and effective tax rate for 2011 reflect the effect of recognizing a net operating loss (NOL) benefit against our taxable income in the U.S. Our income tax expense for 2011 also reflects net tax benefits of $4.5 million relating to the favorable resolution of income tax audits in the U.S. and the impacts of changes in tax laws in Brazil and the State of Michigan.
	As of December 31, 2013 and 2012, we have refundable income taxes of $4.9 million and $4.7 million, respectively, classified as prepaid expenses and other on our Consolidated Balance Sheet. We also have income taxes payable of $2.6 million and $0.5 million classified as other accrued expenses on our Consolidated Balance Sheet as of December 31, 2013 and 2012, respectively. As of December 31, 2013 and 2012, we have accrued value added tax payable of $38.3 million and $27.1 million, respectively, classified as other accrued expenses on our Consolidated Balance Sheet.
	The following is a summary of the significant components of our deferred tax assets and liabilities:
		December 31,
		2013				2012
		(in millions)
	Current deferred tax assets
	Employee benefits	$	14.5			$	16.9
	Inventory	8				12.6
	Prepaid taxes and other	24.6				15.5
	Valuation allowance	(10.7		)		(10.1		)
	Total current deferred tax assets	$	36.4			$	34.9
	Current deferred tax liabilities
	Unrealized foreign exchange gain and other	(0.1		)		(1.4		)
	Current deferred tax asset, net	$	36.3			$	33.5
	Current deferred tax assets and liabilities recognized in our Consolidated Balance Sheets are as follows:
		December 31,
		2013				2012
		(in millions)
	U.S. federal and state deferred tax asset, net	$	17.1			$	23
	Other foreign deferred tax asset, net	19.2				10.5
	Current deferred tax asset, net	$	36.3			$	33.5
	The following is a summary of the significant components of our noncurrent deferred tax assets and liabilities:
		December 31,
		2013				2012
		(in millions)
	Noncurrent deferred tax assets
	Employee benefits	$	161.5			$	200.7
NOL carryforwards	176.9				177.4
Tax credit carryforwards	82.9				79
Capital allowance carryforwards	16				17.9
Fixed assets	10.3				9
Deferred revenue	15.7				20
Capitalized expenditures	113.6				99.3
Other	2.9				4
Valuation allowances	(153.0		)		(156.0		)
Noncurrent deferred tax assets	426.8				451.3
Noncurrent deferred tax liabilities
U.S. tax on unremitted foreign earnings	(85.0		)		(85.2		)
Fixed assets and other	(9.8		)		(9.5		)
Noncurrent deferred tax asset, net	$	332			$	356.6
Noncurrent deferred tax assets and liabilities recognized in our Consolidated Balance Sheets are as follows:
	December 31,
	2013				2012
	(in millions)
U.S. federal and state deferred tax asset, net	$	337.2			$	363.3
Other foreign deferred tax asset (liability), net	(5.2		)		(6.7		)
Noncurrent deferred tax asset, net	$	332			$	356.6
DEFERRED INCOME TAX ASSETS AND LIABILITIES AND VALUATION ALLOWANCES The deferred income tax assets and liabilities previously summarized reflect the impact of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the basis of such assets and liabilities as measured by tax laws. As of December 31, 2013 and December 31, 2012, we had deferred tax assets from domestic and foreign NOL and tax credit carryforwards of $275.8 million and $274.3 million, respectively. Approximately $74.5 million of the deferred tax assets at December 31, 2013 relate to NOL carryforwards or tax credits that can be carried forward indefinitely with the remainder having carryover periods of 5 to 20 years.
Accounting guidance for income taxes requires a deferred tax liability be established for the U.S. tax impact of undistributed earnings of foreign subsidiaries unless it can be shown that these earnings will be permanently reinvested outside the U.S. We believe a portion of these accumulated foreign earnings in certain jurisdictions are likely to be remitted to the U.S. as dividends or intercompany loans and have established a deferred tax liability of $85.0 million and $85.2 million as of December 31, 2013 and 2012, respectively, which represents the estimated tax impact of the undistributed earnings of certain foreign subsidiaries. The remittance of these undistributed earnings may subject us to U.S. income taxes and certain foreign withholding taxes at the time of remittance.
In accordance with the accounting guidance for income taxes, we estimate whether recoverability of our deferred tax assets is “more likely than not,” based on forecasts of taxable income in the related tax jurisdictions.  In this estimate, we use historical results, projected future operating results based upon approved business plans, eligible carry forward periods, tax planning opportunities and other relevant considerations.
As described above, in 2012, we released the valuation allowance against our net federal deferred assets for entities in the United States, resulting in a $337.5 million benefit in our 2012 provision for income taxes. As of December 31, 2013, we have a valuation allowance of approximately $163.7 million related to net deferred tax assets in several foreign jurisdictions and U.S. state and local jurisdictions. At December 31, 2012, our valuation allowance was $166.1 million.
UNRECOGNIZED INCOME TAX BENEFITS To the extent our uncertain tax positions do not meet the “more likely than not” threshold, we have derecognized such positions. To the extent our uncertain tax positions meet the “more likely than not” threshold, we have measured and recorded the highest probable benefit, and have established appropriate reserves for benefits that exceed the amount likely to be sustained upon examination.
A reconciliation of the beginning and ending amounts of unrecognized income tax benefits is as follows:
	Unrecognized Income Tax				Interest and
	Benefits				Penalties
	(in millions)
Balance at January 1, 2011	$	47.6			$	21.4
Increase in prior year tax positions	—				1
Decrease in prior year tax positions	(0.8		)		(2.3		)
Increase in current year tax positions	1.3				—
Settlement	(22.3		)		(12.7		)
Balance at December 31, 2011	$	25.8			$	7.4
Increase in prior year tax positions	—				2.8
Decrease in prior year tax positions	(1.1		)		—
Increase in current year tax positions	0.4				—
Settlement	(4.4		)		—
Balance at December 31, 2012	$	20.7			$	10.2
Increase in prior year tax positions	6.1				0.1
Decrease in prior year tax positions	(4.4		)		(6.2		)
Increase in current year tax positions	4				—
Settlement	(4.7		)		—
Balance at December 31, 2013	$	21.7			$	4.1
At December 31, 2013 and December 31, 2012, we had $21.7 million and $20.7 million of net unrecognized income tax benefits, respectively.
In 2013, 2012 and 2011, we recognized a benefit of $6.1 million, expense of $2.8 million and a benefit of $1.3 million, respectively, of interest and penalties in income tax expense on our Consolidated Statement of Income. We have a liability of $4.1 million and $10.2 million related to the estimated future payment of interest and penalties at December 31, 2013 and 2012, respectively.
We file income tax returns in the U.S. federal jurisdiction, as well as various states and foreign jurisdictions. The Internal Revenue Service (IRS) commenced an examination of our U.S. income tax returns for 2010 and 2011 in 2013. The Mexican tax authorities commenced a transfer pricing examination of our income tax return for 2008 in 2013 and continue with its transfer pricing examination of our 2007 income tax return. We are no longer subject to U.S. federal, state and local, or non-U.S. income tax examinations by tax authorities for years before 2007.
The U.S. federal income tax examination for the years 2004 through 2007 and the Mexico domestic income tax examination for the year 2006 were completed 2011. These settlements resulted in a reduction of a portion of our liability for unrecognized income tax benefits in 2011 and a cash payment of $9.5 million in 2011 and $4.1 million, which was paid in 2012. The U.S. federal income tax examination for the years 2008 and 2009 and the Mexico transfer pricing examination for the year 2006 were settled in 2013. These settlements resulted in a reduction of a portion of our liability for unrecognized income tax benefits and a cash payment of $4.7 million in 2013. At this time, we are not aware of any examinations underway in any other foreign jurisdictions.
Based on the status of the IRS audits and audits outside the U.S., and the protocol of finalizing audits by the relevant tax authorities, it is not possible to estimate the impact of changes, if any, to previously recorded uncertain tax positions. Although it is not possible to predict the timing of the conclusion of all ongoing audits with certainty, we anticipate that the current 2007 audit with the Mexican tax authorities will be completed during 2014 and the current U.S. IRS audits will be completed during 2015. It is possible that a reduction in the unrecognized tax benefits may occur; however, quantification of an estimated range cannot be made at this time

Earnings_Loss_Per_Share_EPS

Earnings (Loss) Per Share (EPS)	12 Months Ended
	Dec. 31, 2013
Earnings (Loss) per Share (EPS) [Abstract]	'
Earnings Per Share [Text Block]	'
		EARNINGS PER SHARE (EPS)
	The following table sets forth the computation of our basic and diluted EPS:
		2013		2012		2011
		(in millions, except per share data)
	Numerator
	Net income attributable to AAM	$	94.5	$	367.7	$	142.8
	Denominators
	Basic shares outstanding -
	Weighted-average shares outstanding	76.7		75.3		74.9
	Effect of dilutive securities -
	Dilutive stock options	0.1		0.1		0.1
	Dilutive warrants	—		—		0.4
	Diluted shares outstanding -
	Adjusted weighted-average shares after assumed conversions	76.8		75.4		75.4
	Basic EPS	$	1.23	$	4.88	$	1.91
	Diluted EPS	$	1.23	$	4.87	$	1.89
	Certain exercisable stock options were excluded in the computations of diluted EPS because the exercise price of these options was greater than the average annual market prices of our stock. The number of stock options outstanding excluded from the calculation of diluted EPS was 2.0 million at year-end 2013, 3.3 million at year-end 2012 and 4.0 million at year-end 2011. The ranges of exercise prices related to these stock options were $19.54 - $40.83 at year-end 2013, $15.58 - $40.83 at year-end 2012 and $15.56 - $40.83 at year-end 2011.
	As part of the 2009 Settlement and Commercial Agreement, we issued to GM five year warrants, which entitled GM to purchase 4.1 million shares of AAM's common stock at an exercise price of $2.76 per share. In 2011, GM exercised these warrants. In accordance with the cashless exercise option available in the agreement, we issued 3.3 million net shares of common stock to GM.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies [Abstract]	'
Commitments and Contingencies Disclosure [Text Block]	'
	10. COMMITMENTS AND CONTINGENCIES
	PURCHASE COMMITMENTS Obligated purchase commitments for capital expenditures and related project expenses were approximately $161.4 million at December 31, 2013 and $231.9 million at December 31, 2012.
	LEGAL PROCEEDINGS We are involved in various legal proceedings incidental to our business. Although the outcome of these matters cannot be predicted with certainty, we do not believe that any of these matters, individually or in the aggregate, will have a material effect on our financial condition, results of operations or cash flows.
	We are subject to various federal, state, local and foreign environmental and occupational safety and health laws, regulations and ordinances, including those regulating air emissions, water discharge, waste management and environmental cleanup. We will continue to closely monitor our environmental conditions to ensure that we are in compliance with all laws, regulations and ordinances. We have made, and will continue to make, capital and other expenditures to comply with environmental requirements, including recurring administrative costs. Such expenditures were not significant during 2013, 2012 and 2011.
	In 2012, the International UAW filed suit against AAM alleging that we violated certain provisions of the collective bargaining agreement covering represented hourly associates at the Detroit Manufacturing Complex and Cheektowaga Manufacturing Facility related to pension and postretirement benefits. In 2012, we recorded $28.7 million in cost of goods sold related to pension and postretirement benefits to be provided to certain eligible UAW associates as a result of our election to apply MAP-21 and the subsequent recertification of our U.S. hourly pension plan.  This suit was settled in 2012.
	ENVIRONMENTAL OBLIGATIONS Due to the nature of our manufacturing operations, we have legal obligations to perform asset retirement activities pursuant to federal, state, and local requirements. The process of estimating environmental liabilities is complex. Significant uncertainty may exist related to the timing and method of the settlement of these obligations. Therefore, these liabilities are not reasonably estimable until a triggering event occurs that allows us to estimate a range and assess the probabilities of potential settlement dates and the potential methods of settlement. As a result of a plant closure in 2011, the methods and timing of certain environmental liabilities related to this facility became reasonably estimable.  See Note 2 - Restructuring Actions for more detail on our environmental liabilities, included in asset retirement obligations.
	In the future, we will update our estimated costs and potential settlement dates and methods and their associated probabilities based on available information. Any update may change our estimate and could result in a material adjustment to this liability.
	PRODUCT WARRANTIES We record a liability for estimated warranty obligations at the dates our products are sold. These estimates are established using sales volumes and internal and external warranty data where there is no payment history and historical information about the average cost of warranty claims for customers with prior claims. We estimate our costs based on the contractual arrangements with our customers, existing customer warranty terms and internal and external warranty data, which includes a determination of our warranty claims and take actions to improve product quality and minimize warranty claims. We continuously evaluate these estimates and our customer's administration of their warranty programs. We closely monitor actual warranty claim data and adjust the liability, as necessary, on a quarterly basis.
	We recorded $2.3 million and $9.9 million of expense in 2013 and 2012, respectively, related to a field action with our largest customer. In 2013, we made warranty payments of $12.3 million, of which $11.3 million related to this field action. During 2013, we also made adjustments to our warranty accrual to reflect revised estimates regarding our projected future warranty obligations.
	The following table provides a reconciliation of changes in the product warranty liability:
		December 31,
		2013			2012
		(in millions)
	Beginning balance	$	29.1		$	13.4
	Accruals	12.8			23
	Settlements	(12.3		)	(0.9		)
	Adjustments to prior period accruals	(15.0		)	(6.4		)
	Foreign currency translation	(0.3		)	—
	Ending balance	$	14.3		$	29.1

Reclassifications_out_of_Accum

Reclassifications out of Accumulated Other Comprehensive Income Reclassifications out of Accumulated Other Comprehensive Income	12 Months Ended
	Dec. 31, 2013
Reclassifications out of Accumulated Other Comprehensive Income [Abstract]	'
Disclosure of Reclassification Amount [Text Block]	'
	11. RECLASSIFICATIONS OUT OF ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)
	Reclassification adjustments and other activity impacting accumulated other comprehensive income (loss) (AOCI) during the year ended December 31, 2013 are as follows (in millions):
		Defined Benefit Plans				Foreign Currency Translation Adjustments			Unrecognized Gain on Derivatives				Total
	Balance at December 31, 2012	$	(274.5	)		$	7.6		$	2.3			$	(264.6	)
	Other comprehensive income (loss) before reclassifications	67.7			(a)	(26.2		)	0.8				42.3
	Amounts reclassified from accumulated other comprehensive income (loss) into net income	8.9			(a)(b)	—			(2.8		)	(c)	6.1
	Net current period other comprehensive income (loss)	76.6				(26.2		)	(2.0		)		48.4
	Balance at December 31, 2013	$	(197.9	)		$	(18.6	)	$	0.3			$	(216.2	)
	(a) These amounts are net of tax of $(36.7) million and $(4.6) million for other comprehensive income before reclassifications and the amounts reclassified from AOCI, respectively, for the year ended December 31, 2013.
	(b) The net amount reclassified from AOCI included $4.7 million in cost of goods sold (COGS) and $4.2 million in selling, general & administrative expenses for the year ended December 31, 2013.
	(c) The amounts reclassified from AOCI are included in COGS.

Segment_and_Geographic_Informa

Segment and Geographic Information	12 Months Ended
	Dec. 31, 2013
Segment and Geographic Information [Abstract]	'
Segment Reporting Disclosure [Text Block]	'
	12. SEGMENT AND GEOGRAPHIC INFORMATION
	We operate in one reportable segment: the manufacture, engineer, design and validation of driveline systems and related components and chassis modules for light trucks, SUVs, passenger cars, crossover vehicles and commercial vehicles. Financial information relating to our operations by geographic area is presented in the following table. Net sales are attributed to countries based upon location of customer. Long-lived assets exclude deferred income taxes.
		December 31,
		2013		2012		2011
		(in millions)
	Net sales
	United States	$	1,682.00	$	1,576.60	$	1,587.30
	Canada	74.4		75		60.8
	Mexico	865.6		755.1		678.5
	South America	201.1		216.4		134.8
	Asia	255.2		214.5		33.2
	Europe and other	129		93.3		90.4
	Total net sales	$	3,207.30	$	2,930.90	$	2,585.00
	Long-lived assets
	United States	$	850	$	865.3	$	845.7
	Mexico	469.3		417.7		384.9
	South America	100.2		113.3		131.9
	Asia	176.7		159		131.7
	Europe	93.2		72.5		51.3
	Total long-lived assets	$	1,689.40	$	1,627.80	$	1,545.50

Unaudited_Quarterly_Financial_

Unaudited Quarterly Financial Data	12 Months Ended
	Dec. 31, 2013
Unaudited Quarterly Financial Data [Abstract]	'
Quarterly Financial Information [Text Block]	'
	13. UNAUDITED QUARTERLY FINANCIAL DATA
		Three Months Ended,
		31-Mar		30-Jun		30-Sep			31-Dec
		(in millions, except per share data)
	2013
	Net sales	$	755.6	$	799.6	$	820.8		$	831.3
	Gross profit	104.3		122.2		125.3			126.9
	Net income	7.3		25.8		31.6			29.8
	Net income attributable to AAM	7.3		25.8		31.6			29.8
	Basic EPS (1)	$	0.1	$	0.34	$	0.41		$	0.39
	Diluted EPS (1)	$	0.1	$	0.34	$	0.41		$	0.39
	2012
	Net sales	$	751.5	$	739.8	$	702.9		$	736.7
	Gross profit	139.2		85.8		90.7			84
	Net income (loss)	50.3		4.7		(8.2		)	319.9
	Net income (loss) attributable to AAM	51.2		4.7		(8.1		)	319.9
	Basic EPS (1)	$	0.68	$	0.06	$	(0.11	)	$	4.21
	Diluted EPS (1)	$	0.68	$	0.06	$	(0.11	)	$	4.21
	(1) Full year basic and diluted EPS will not necessarily agree to the sum of the four quarters because each quarter is a separate calculation.

Supplemental_Guarantor_Condens

Supplemental Guarantor Condensed Consolidating Financial Statements	12 Months Ended
	Dec. 31, 2013
Supplemental Guarantor Condensed Consolidating Financial Statements [Abstract]	'
Supplemental Guarantor Disclosure [Text Block]	'
	14. SUPPLEMENTAL GUARANTOR CONDENSED CONSOLIDATING FINANCIAL STATEMENTS
	Holdings has no significant assets other than its 100% ownership in AAM, Inc. and no direct subsidiaries other than AAM, Inc. The 7.75% Notes, 6.625% Notes, 6.25% Notes and 5.125% Notes are senior unsecured obligations of AAM Inc.; all of which are fully and unconditionally guaranteed by Holdings and substantially all domestic subsidiaries of AAM, Inc., which are 100% indirectly owned by Holdings.
	These Condensed Consolidating Financial Statements are prepared under the equity method of accounting whereby the investments in subsidiaries are recorded at cost and adjusted for the parent's share of the subsidiaries' cumulative results of operations, capital contributions and distributions, and other equity changes.
	Condensed Consolidating Statements of Income
	2013	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
		(in millions)
	Net sales
	External	$	—		$	773.6		$	226		$	2,207.70		$	—		$	3,207.30
	Intercompany	—			15.3			226.1			14			(255.4		)	—
	Total net sales	—			788.9			452.1			2,221.70			(255.4		)	3,207.30
	Cost of goods sold	—			769.4			389			1,825.60			(255.4		)	2,728.60
	Gross profit	—			19.5			63.1			396.1			—			478.7
	Selling, general and administrative expenses	—			182.4			0.1			55.9			—			238.4
	Operating income (loss)	—			(162.9		)	63			340.2			—			240.3
	Non-operating income (expense), net	—			(155.1		)	10.7			(9.6		)	—			(154.0		)
	Income (loss) before income taxes	—			(318.0		)	73.7			330.6			—			86.3
	Income tax expense (benefit)	—			(24.9		)	0.9			15.8			—			(8.2		)
	Earnings (loss) from equity in subsidiaries	94.5			167			(21.7		)	—			(239.8		)	—
	Net income (loss) before royalties and dividends	94.5			(126.1		)	51.1			314.8			(239.8		)	94.5
	Royalties and dividends	—			220.6			—			(220.6		)	—			—
	Net income after royalties and dividends	94.5			94.5			51.1			94.2			(239.8		)	94.5
	Net loss attributable to noncontrolling interests	—			—			—			—			—			—
	Net income attributable to AAM	$	94.5		$	94.5		$	51.1		$	94.2		$	(239.8	)	$	94.5
	Other comprehensive income (loss), net of tax	48.4			48.4			(7.2		)	(10.8		)	(30.4		)	48.4
	Comprehensive income attributable to AAM	$	142.9		$	142.9		$	43.9		$	83.4		$	(270.2	)	$	142.9
	2012	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Net sales
	External	$	—		$	704.8		$	214.4		$	2,011.70		$	—		$	2,930.90
	Intercompany	—			18.6			226.8			25.2			(270.6		)	—
	Total net sales	—			723.4			441.2			2,036.90			(270.6		)	2,930.90
	Cost of goods sold	—			709.8			389.8			1,702.20			(270.6		)	2,531.20
	Gross profit	—			13.6			51.4			334.7			—			399.7
	Selling, general and administrative expenses	—			186.5			—			56.8			—			243.3
	Operating income (loss)	—			(172.9		)	51.4			277.9			—			156.4
	Non-operating income (expense), net	—			(135.2		)	(2.2		)	12.5			—			(124.9		)
	Income (loss) before income taxes	—			(308.1		)	49.2			290.4			—			31.5
	Income tax expense (benefit)	—			(343.9		)	(5.5		)	14.2			—			(335.2		)
	Earnings (loss) from equity in subsidiaries	367.7			79			(49.2		)	—			(397.5		)	—
	Net income before royalties and dividends	367.7			114.8			5.5			276.2			(397.5		)	366.7
	Royalties and dividends	—			252.9			—			(252.9		)	—			—
	Net income after royalties and dividends	367.7			367.7			5.5			23.3			(397.5		)	366.7
	Net loss attributable to noncontrolling interests	—			—			—			1			—			1
	Net income attributable to AAM	$	367.7		$	367.7		$	5.5		$	24.3		$	(397.5	)	$	367.7
	Other comprehensive loss, net of tax	(60.5		)	(60.5		)	(10.1		)	(3.6		)	74.2			(60.5		)
	Foreign currency translation adjustments attributable to noncontrolling interests	0.3			0.3			—			0.3			(0.6		)	0.3
	Comprehensive income (loss) attributable to AAM	$	306.9		$	306.9		$	(4.6	)	$	20.4		$	(322.7	)	$	306.9
	2011	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Net sales
	External	$	—		$	777.7		$	195.3		$	1,612.00		$	—		$	2,585.00
	Intercompany	—			25.1			189.8			12.7			(227.6		)	—
	Total net sales	—			802.8			385.1			1,624.70			(227.6		)	2,585.00
	Cost of goods sold	—			727			334.2			1,296.30			(227.6		)	2,129.90
	Gross profit	—			75.8			50.9			328.4			—			455.1
	Selling, general and administrative expenses	—			192			—			39.7			—			231.7
	Operating income (loss)	—			(116.2		)	50.9			288.7			—			223.4
	Non-operating income (expense), net	—			(91.8		)	1			5.5			—			(85.3		)
	Income (loss) before income taxes	—			(208		)	51.9			294.2			—			138.1
	Income tax expense (benefit)	—			(5.2		)	1.2			5			—			1
	Earnings (loss) from equity in subsidiaries	142.8			165.5			(37.7		)	—			(270.6		)	—
	Net income (loss) before royalties and dividends	142.8			(37.3		)	13			289.2			(270.6		)	137.1
	Royalties and dividends	—			180.1			—			(180.1		)	—			—
	Net income after royalties and dividends	142.8			142.8			13			109.1			(270.6		)	137.1
	Net loss attributable to noncontrolling interests	—			—			—			5.7			—			5.7
Net income attributable to AAM	$	142.8		$	142.8		$	13		$	114.8		$	(270.6	)	$	142.8
Other comprehensive loss, net of tax	(97.6		)	(97.6		)	(29.0		)	(35.6		)	162.2			(97.6		)
Foreign currency translation adjustments attributable to noncontrolling interests	0.2			0.2			—			0.2			(0.4		)	0.2
Comprehensive income (loss) attributable to AAM	$	45		$	45		$	(16.0	)	$	79		$	(108.0	)	$	45
Condensed Consolidating Balance Sheets
2013	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
Assets	(in millions)
Current assets
Cash and cash equivalents	$	—		$	36.9		$	—		$	117.1		$	—		$	154
Accounts receivable, net	—			102.7			25.6			330.2			—			458.5
Inventories, net	—			62.4			34.2			165.2			—			261.8
Other current assets	—			43.8			3.2			76.5			—			123.5
Total current assets	—			245.8			63			689			—			997.8
Property, plant and equipment, net	—			239.8			83			735.7			—			1,058.50
Goodwill	—			—			147.8			8.6			—			156.4
Other assets and deferred charges	—			671.7			44.8			99.8			—			816.3
Investment in subsidiaries	360.5			1,233.20			—			—			(1,593.7		)	—
Total assets	$	360.5		$	2,390.50		$	338.6		$	1,533.10		$	(1,593.7	)	$	3,029.00
Liabilities and stockholders' equity (deficit)
Current liabilities
Accounts payable	$	—		$	106.2		$	44.5		295.1			$	—		$	445.8
Other current liabilities	—			120.4			4.1			96.8			—			221.3
Total current liabilities	—			226.6			48.6			391.9			—			667.1
Intercompany payable (receivable)	326.9			(390.1		)	(219.5		)	282.7			—			—
Long-term debt	—			1,500.00			5.3			53.8			—			1,559.10
Investment in subsidiaries obligation	—			—			15.2			—			(15.2		)	—
Other long-term liabilities	—			693.5			0.5			75.2			—			769.2
Total liabilities	326.9			2,030.00			(149.9		)	803.6			(15.2		)	2,995.40
Total AAM Stockholders' equity	33.6			360.5			488.5			729.5			(1,578.5		)	33.6
Noncontrolling interests in subsidiaries	—			—			—			—			—			—
Total stockholders' equity	33.6			360.5			488.5			729.5			(1,578.5		)	33.6
Total liabilities and stockholders' equity	$	360.5		$	2,390.50		$	338.6		$	1,533.10		$	(1,593.7	)	$	3,029.00
2012	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
Assets
Current assets
Cash and cash equivalents	$	—		$	10.6		$	—		$	51.8		$	—		$	62.4
Accounts receivable, net	—			94.4			25.3			343.7			—			463.4
Inventories, net	—			48.7			31.6			144			—			224.3
Other current assets	—			48.8			3.5			69.7			—			122
Total current assets	—			202.5			60.4			609.2			—			872.1
Property, plant and equipment, net	—			250.4			84.2			675.1			—			1,009.70
Goodwill	—			—			147.8			8.6			—			156.4
Other assets and deferred charges	—			706.1			40			81.7			—			827.8
Investment in subsidiaries	202.9			1,094.60			—			—			(1,297.5		)	—
Total assets	$	202.9		$	2,253.60		$	332.4		$	1,374.60		$	(1,297.5	)	$	2,866.00
Liabilities and stockholders' equity (deficit)
Current liabilities
Accounts payable	$	—		$	91.4		$	37.3		$	267.4		$	—		$	396.1
Other current liabilities	—			124.5			3.8			76.4			—			204.7
Total current liabilities	—			215.9			41.1			343.8			—			600.8
Intercompany payable (receivable)	323.7			(420.6		)	(188.7		)	285.6			—			—
Long-term debt	—			1,387.50			5.6			61			—			1,454.10
Investment in subsidiaries obligation	—			—			7.6			—			(7.6		)	—
Other long-term liabilities	—			867.9			1.2			62.8			—			931.9
Total liabilities	323.7			2,050.70			(133.2		)	753.2			(7.6		)	2,986.80
Total AAM Stockholders' equity (deficit)	(120.8		)	202.9			465.6			621.4			(1,289.9		)	(120.8		)
Noncontrolling interests in subsidiaries	—			—			—			—			—			—
Total stockholders' equity (deficit)	(120.8		)	202.9			465.6			621.4			(1,289.9		)	(120.8		)
Total liabilities and stockholders' equity (deficit)	$	202.9		$	2,253.60		$	332.4		$	1,374.60		$	(1,297.5	)	$	2,866.00
Condensed Consolidating Statements of Cash Flows
2013	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	(in millions)
Net cash provided by (used in) operating activities	$	—		$	(70.4	)	$	84.9		$	208.5		$	—		$	223
Investing activities
Purchases of property, plant and equipment	—			(61.2		)	(12.5		)	(178.2		)	—			(251.9		)
Proceeds from sale of property, plant and equipment	—			5.1			0.5			3.5			—			9.1
Proceeds from sale-leaseback of equipment	—			24.1			—			—			—			24.1
Net cash used in investing activities	—			(32.0		)	(12.0		)	(174.7		)	—			(218.7		)
Financing activities
Net debt activity	—			110.1			(0.3		)	(5.0		)	—			104.8
Intercompany activity	0.4			34.1			(72.6		)	38.1			—			—
Debt issuance costs	—			(16.6		)	—			(0.1		)	—			(16.7		)
Employee stock option exercises	—			1.1			—			—			—			1.1
Purchase of treasury stock	(0.4		)	—			—			—			—			(0.4		)
Net cash provided by (used in) financing activities	—			128.7			(72.9		)	33			—			88.8
Effect of exchange rate changes on cash	—			—			—			(1.5		)	—			(1.5		)
Net increase in cash and cash equivalents	—			26.3			—			65.3			—			91.6
Cash and cash equivalents at beginning of period	—			10.6			—			51.8			—			62.4
Cash and cash equivalents at end of period	$	—		$	36.9		$	—		$	117.1		$	—		$	154
2012	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
Net cash provided by (used in) operating activities	$	—		$	(228.2	)	$	56.8		$	(4.1	)	$	—		$	(175.5	)
Investing activities
Purchases of property, plant and equipment	—			(59.4		)	(9.0		)	(139.2		)	—			(207.6		)
Proceeds from sale of property, plant and equipment	—			7			—			3.1			—			10.1
Proceeds from sale-leaseback of equipment	—			12.1			—			—			—			12.1
Net cash used in investing activities	—			(40.3		)	(9.0		)	(136.1		)	—			(185.4		)
Financing activities
Net debt activity	—			257.9			(0.2		)	16.2			—			273.9
Intercompany activity	5.9			(52.0		)	(47.6		)	93.7			—			—
Debt issuance costs	—			(10.6		)	—			—			—			(10.6		)
Employee stock option exercises	—			0.1			—			—			—			0.1
Purchase of treasury stock	(5.9		)	—			—			—			—			(5.9		)
Purchase of noncontrolling interest	—			—			—			(4.0		)	—			(4.0		)
Net cash provided by (used in) financing activities	—			195.4			(47.8		)	105.9			—			253.5
Effect of exchange rate changes on cash	—			—			—			0.6			—			0.6
Net decrease in cash and cash equivalents	—			(73.1		)	—			(33.7		)	—			(106.8		)
Cash and cash equivalents at beginning of period	—			83.7			—			85.5			—			169.2
Cash and cash equivalents at end of period	$	—		$	10.6		$	—		$	51.8		$	—		$	62.4
2011	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
Net cash provided by (used in) operating activities	$	—		$	(119.3	)	$	40.1		$	22.9		$	—		$	(56.3	)
Investing activities
Purchases of property, plant and equipment	—			(43.9		)	(4.9		)	(114.3		)	—			(163.1		)
Proceeds from sale of property, plant and equipment	—			1.5			—			7.4			—			8.9
Acquisition, net	—			—			(16.5		)	—			—			(16.5		)
Purchase buyouts of leased equipment	—			(13.4		)	—			—			—			(13.4		)
Net cash used in investing activities	—			(55.8		)	(21.4		)	(106.9		)	—			(184.1		)
Financing activities
Net debt activity	—			159.6			(0.2		)	14.2			—			173.6
Intercompany activity	0.1			37.9			(18.5		)	(19.5		)	—			—
Debt issuance costs	—			(10.9		)	—			—			—			(10.9		)
Employee stock option exercises, including tax benefit	—			4.6			—			—			—			4.6
Purchase of treasury stock	(0.1		)	—			—			—			—			(0.1		)
Net cash provided by (used in) financing activities	—			191.2			(18.7		)	(5.3		)	—			167.2
Effect of exchange rate changes on cash	—			—			—			(2.2		)	—			(2.2		)
Net increase (decrease) in cash and cash equivalents	—			16.1			—			(91.5		)	—			(75.4		)
Cash and cash equivalents at beginning of period	—			67.6			—			177			—			244.6
Cash and cash equivalents at end of period	$	—		$	83.7		$	—		$	85.5		$	—		$	169.2

Schedule_II_Valuation_and_Qual

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2012
Exhibits and Financial Statements Schedules [Abstract]	'
Schedule of Valuation and Qualifying Accounts Disclosure [Text Block]	'
	Schedule II - VALUATION AND QUALIFYING ACCOUNTS
				Additions -
		Balance at		Charged to		Deductions -			Balance
		Beginning of		Costs and		See Notes			At End of
		Period		Expenses		Below			Period
		(in millions)
	Year Ended December 31, 2011:
	Allowance for doubtful accounts	$	6.2	$	3.3	$	4	(1)	$	5.5
	Allowance for deferred taxes	560.9		14.6		148.6		(3)	426.9
	Inventory valuation allowance	27.7		6.3		7.3		(2)	26.7
	Year Ended December 31, 2012:
	Allowance for doubtful accounts	5.5		2		1		(1)	6.5
	Allowance for deferred taxes	426.9		80.9		341.7		(4)	166.1
	Inventory valuation allowance	26.7		7.9		13.6		(2)	21
	Year Ended December 31, 2013:
	Allowance for doubtful accounts	6.5		2.3		3.9		(1)	4.9
	Allowance for deferred taxes	166.1		14		16.4			163.7
	Inventory valuation allowance	21		19.4		13.1		(2)	27.3
	-1	Uncollectible accounts charged off net of recoveries.
	-2	Primarily relates to inventory adjustments for physical quantity discrepancies and write-offs of excess and obsolete inventories.
	-3	Primarily relates to the utilization of some of the 2009 NOL carryover, an adjustment of the deferred tax liability for the U.S. tax impact of undistributed earnings of certain foreign subsidiaries and the settlement of the U.S. audit appeals for the 2004 to 2007 tax years.
	-4	Primarily relates to the reversal of the valuation allowance against our net federal U.S. deferred tax assets.

Organization_and_Basis_of_Pres1

Organization and Basis of Presentation Level 2 Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Organization and Summary of Significant Accounting Policies [Abstract]	'
Consolidation, Policy [Policy Text Block]	'
	PRINCIPLES OF CONSOLIDATION We include the accounts of Holdings and its subsidiaries in our consolidated financial statements. We eliminate the effects of all intercompany transactions, balances and profits in our consolidation.
Revenue Recognition, Policy [Policy Text Block]	'
	REVENUE RECOGNITION We recognize revenue when products are shipped to our customers and title transfers under standard commercial terms or when realizable in accordance with our commercial agreements. If we are uncertain as to whether we will be successful collecting a balance in accordance with our understanding of a commercial agreement, we do not recognize the revenue or cost recovery until such time as the uncertainty is removed.
	In 2009, we entered into a settlement and commercial agreement (2009 Settlement and Commercial Agreement) with General Motors Company (GM). As part of this agreement, we received $110.0 million from GM, of which we recorded $79.7 million as deferred revenue.  As of December 31, 2013, our deferred revenue related to the 2009 Settlement and Commercial Agreement is $45.5 million, $8.0 million of which is classified as a current liability and $37.5 million of which is recorded as a noncurrent liability on our Consolidated Balance Sheet.  We recognize this deferred revenue into revenue on a straight-line basis over 120 months, which ends September 2019 and is the period that we expect GM to benefit under the 2009 Settlement and Commercial Agreement.  We recognized revenue of $8.0 million, in 2013, 2012 and 2011 related to this agreement.
	In 2008, we entered into an agreement with GM to provide financial assistance to support the transition of our United Automobile, Aerospace and Agricultural Implement Workers of America (UAW) represented legacy labor at our original U.S. locations upon the resolution of the strike called by the International UAW (2008 AAM - GM Agreement).  Pursuant to this agreement, GM provided us $115.0 million in 2008 and $60.0 million in 2009. In total, we recorded deferred revenue of $213.7 million as a result of the 2008 AAM - GM Agreement, which included $38.7 million related to the fair value of the liability GM assumed for postretirement healthcare and life insurance coverage provided to UAW represented transitioned associates with earned credited service from AAM that have or will retire under plans operated by GM. We recognized this deferred revenue into revenue on a straight-line basis over a 45 month period, which ended February 2012 and was consistent with the period that we expected GM to benefit from the payments provided to us under the 2008 AAM - GM Agreement. We recognized $9.5 million of revenue in 2012 and $57.0 million of revenue in 2011 related to the 2008 AAM - GM Agreement.
	As of December 31, 2013, the majority of the remaining deferred revenue primarily relates to customer payments to implement capacity programs, which is generally recognized into revenue over the life of these programs. We recognized $10.5 million, $13.1 million and $15.6 million of revenue for these programs in 2013, 2012 and 2011, respectively.
Research and Development Expense, Policy [Policy Text Block]	'
	RESEARCH AND DEVELOPMENT (R&D) COSTS We expense R&D, as incurred, in selling, general and administrative expenses on our Consolidated Statement of Income. R&D spending was $103.4 million, net of engineering, design and development recoveries, $123.4 million and $113.6 million in 2013, 2012 and 2011, respectively.
Cash and Cash Equivalents, Policy [Policy Text Block]	'
	CASH AND CASH EQUIVALENTS Cash and cash equivalents include all cash balances and highly liquid investments in money market funds with maturities of 90 days or less at the time of purchase.
Trade and Other Accounts Receivable, Policy [Policy Text Block]	'
	ACCOUNTS RECEIVABLE The majority of our accounts receivable are due from original equipment manufacturers (OEMs) in the automotive industry and are past due when payment is not received within the stated terms. Trade accounts receivable for our largest customer, GM, are generally due within approximately 50 days from the date of receipt.
	Amounts due from customers are stated net of allowances for doubtful accounts. We determine our allowances by considering factors such as the length of time accounts are past due, our previous loss history, the customer's ability to pay its obligation to us, and the condition of the general economy and the industry as a whole. The allowance for doubtful accounts was $4.9 million and $6.5 million as of December 31, 2013 and 2012, respectively. We write-off accounts receivable when they become uncollectible.
Property, Plant and Equipment, Preproduction Design and Development Costs [Policy Text Block]	'
	CUSTOMER TOOLING AND PRE-PRODUCTION COSTS RELATED TO LONG-TERM SUPPLY AGREEMENTS Engineering, R&D, and other pre-production design and development costs for products sold on long-term supply arrangements are expensed as incurred unless we have a contractual guarantee for reimbursement from the customer. Costs for tooling used to make products sold on long-term supply arrangements for which we have either title to the assets or the non-cancelable right to use the assets during the term of the supply arrangement are capitalized in property, plant and equipment. Capitalized items and customer receipts in excess of tooling costs specifically related to a supply arrangement are amortized over the shorter of the term of the arrangement or over the estimated useful lives of the related assets.
Inventory, Policy [Policy Text Block]	'
	INVENTORIES We state our inventories at the lower of cost or market.  The cost of our inventories is determined using the FIFO method.  When we determine that our gross inventories exceed usage requirements, or if inventories become obsolete or otherwise not saleable, we record a provision for such loss as a component of our inventory accounts.
	Inventories consist of the following:
		December 31,
		2013				2012
		(in millions)
	Raw materials and work-in-progress	$	263.4			$	220.3
	Finished goods	25.7				25
	Gross inventories	289.1				245.3
	Inventory valuation reserves	(27.3		)		(21.0		)
	Inventories, net	$	261.8			$	224.3
Property, Plant and Equipment, Policy [Policy Text Block]	'
	PROPERTY, PLANT AND EQUIPMENT We state property, plant and equipment, including amortizable tooling, at historical cost, as adjusted for impairments. Construction in progress includes costs incurred for the construction of buildings and building improvements, and machinery and equipment in process. Repair and maintenance costs that do not extend the useful life or otherwise improve the utility of the asset beyond its existing useful state are expensed in the period incurred.
	We record depreciation and tooling amortization on the straight-line method over the estimated useful lives of the depreciable assets. Depreciation and tooling amortization amounted to $151.8 million, $130.9 million and $123.7 million in 2013, 2012 and 2011, respectively.
	Property, plant and equipment consists of the following:
		Estimated		December 31,
		Useful Lives		2013				2012
		(years)		(in millions)
	Land			$	29.5			$	27.8
	Land improvements	15-Oct		18.9				17.8
	Buildings and building improvements	15-40		306.6				293.3
	Machinery and equipment	3-12		1,648.60				1,512.60
	Construction in progress			95.1				123.1
				2,098.70				1,974.60
	Accumulated depreciation and amortization			(1,040.2		)		(964.9		)
	Property, plant and equipment, net			$	1,058.50			$	1,009.70
	PROPERTY, PLANT AND EQUIPMENT We state property, plant and equipment, including amortizable tooling, at historical cost, as adjusted for impairments. Construction in progress includes costs incurred for the construction of buildings and building improvements, and machinery and equipment in process. Repair and maintenance costs that do not extend the useful life or otherwise improve the utility of the asset beyond its existing useful state are expensed in the period incurred.
	We record depreciation and tooling amortization on the straight-line method over the estimated useful lives of the depreciable assets. Depreciation and tooling amortization amounted to $151.8 million, $130.9 million and $123.7 million in 2013, 2012 and 2011, respectively.
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	'
	IMPAIRMENT OF LONG-LIVED ASSETS When impairment indicators exist, we evaluate the carrying value of long-lived assets for potential impairment. We consider projected future undiscounted cash flows, trends and other circumstances in making such estimates and evaluations. If impairment is deemed to exist, the carrying amount of the asset is adjusted based on its fair value. Recoverability of assets “held for use” is determined by comparing the forecasted undiscounted cash flows of the operations to which the assets relate to their carrying amount. When the carrying value of an asset group exceeds its fair value and is therefore nonrecoverable, those assets are written down to fair value. Fair value is determined based on market prices, when available, or a discounted cash flow analysis performed using management estimates. See Note 2 - Restructuring Actions for detail on our 2012 asset impairment.
Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]	'
	GOODWILL We record goodwill when the purchase price of acquired businesses exceeds the value of their identifiable net tangible and intangible assets acquired. We periodically evaluate goodwill for impairment in accordance with the accounting guidance for goodwill and other indefinite-lived intangibles. We completed impairment tests in 2013 and 2012 and concluded that there was no impairment of our goodwill. The following table provides a reconciliation of changes in goodwill:
		December 31,
		2013				2012
		(in millions)
	Beginning balance	$	156.4			$	155.9
	Foreign currency translation	—				0.5
	Ending balance	$	156.4			$	156.4
Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block]	'
	INTANGIBLE ASSETS We are currently in the process of developing and testing global enterprise resource planning (ERP) systems to upgrade many of our existing operating and financial systems. In connection with the development of these ERP systems, we recorded an intangible asset of $7.8 million in 2013 related to costs incurred to obtain software licenses from a third party, as well as costs to design and develop this internal-use software. This intangible asset is classified as other assets and deferred charges on our Consolidated Balance Sheet and will be amortized over the estimated useful life of our ERP systems. We recorded $0.1 million of expense for the amortization of this intangible asset in 2013.
	As part of the formation of e-AAM, we recorded intangible assets of $8.7 million in 2010, which represented the fair value of a GM license agreement for technology developed by Saab Automobile AB (Saab) when it was a subsidiary of GM, in-process research and development technology and a long-term supply agreement with Saab. In 2011, Saab, our former partner in the e-AAM joint venture, filed for bankruptcy and entered into liquidation status. As a result, in 2011, we recorded a $1.6 million impairment charge to selling, general and administrative expenses to write off the intangible asset associated with the long-term supply agreement with Saab. These intangible assets are classified as other assets and deferred charges on our Consolidated Balance Sheet and we expect to begin amortizing the assets on a straight-line basis over their estimated useful lives once development of the related technology is complete and we begin utilizing these assets.
	We recorded an intangible asset of $9.6 million as of December 31, 2008 which represents the fair value of the customer relationships acquired as part of an asset purchase agreement with FormTech Industries LLC. We recorded $1.9 million of expense for the amortization of this intangible asset in each of the years 2013, 2012 and 2011, and this intangible asset has been fully amortized as of December 31, 2013. This intangible asset was amortized on a straight-line basis over its estimated useful life of five years.
Debt, Policy [Policy Text Block]	'
	DEBT ISSUANCE COSTS The costs related to the issuance or modification of long-term debt are deferred and amortized into interest expense over the life of each debt issue. As of December 31, 2013 and December 31, 2012, our unamortized debt issuance costs were $35.6 million and $33.0 million, respectively. Deferred amounts associated with the extinguishment of debt are expensed and classified as debt refinancing and redemption costs on our Consolidated Statement of Income.
Derivatives, Policy [Policy Text Block]	'
	DERIVATIVES We recognize all derivatives on the balance sheet at fair value. If a derivative qualifies under the accounting guidance as a hedge, depending on the nature of the hedge, changes in the fair value of the derivative are either offset against the change in fair value of the hedged asset, liability or firm commitment through earnings or recognized in other comprehensive income until the hedged item is recognized in earnings. The ineffective portion of a derivative's change in fair value, and changes in the fair value of derivatives that do not qualify as hedges, are immediately recognized in earnings. See Note 4 - Derivatives and Risk Management, for more detail on our derivatives.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	'
	CURRENCY TRANSLATION We translate the assets and liabilities of our foreign subsidiaries to U.S. dollars at end-of-period exchange rates. We translate the income statement elements of our foreign subsidiaries to U.S. dollars at average-period exchange rates. We report the effect of translation for our foreign subsidiaries that use the local currency as their functional currency as a separate component of stockholders' deficit. Gains and losses resulting from the remeasurement of assets and liabilities in a currency other than the functional currency of a subsidiary are reported in current period income. We also report any gains and losses arising from transactions denominated in a currency other than the functional currency of a subsidiary in current period income.
Use of Estimates, Policy [Policy Text Block]	'
	USE OF ESTIMATES In order to prepare consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (GAAP), we are required to make estimates and assumptions that affect the reported amounts and disclosures in our consolidated financial statements. Actual results could differ from those estimates.

Organization_and_Basis_of_Pres2

Organization and Basis of Presentation Level 3 (Tables)	12 Months Ended
	Dec. 31, 2013
Organization and Summary of Significant Accounting Policies [Abstract]	'
Schedule of Inventory, Current [Table Text Block]	'
	Inventories consist of the following:
		December 31,
		2013				2012
		(in millions)
	Raw materials and work-in-progress	$	263.4			$	220.3
	Finished goods	25.7				25
	Gross inventories	289.1				245.3
	Inventory valuation reserves	(27.3		)		(21.0		)
	Inventories, net	$	261.8			$	224.3
Property, Plant and Equipment [Table Text Block]	'
	Property, plant and equipment consists of the following:
		Estimated		December 31,
		Useful Lives		2013				2012
		(years)		(in millions)
	Land			$	29.5			$	27.8
	Land improvements	15-Oct		18.9				17.8
	Buildings and building improvements	15-40		306.6				293.3
	Machinery and equipment	3-12		1,648.60				1,512.60
	Construction in progress			95.1				123.1
				2,098.70				1,974.60
	Accumulated depreciation and amortization			(1,040.2		)		(964.9		)
	Property, plant and equipment, net			$	1,058.50			$	1,009.70
Schedule of Goodwill [Table Text Block]	'
	The following table provides a reconciliation of changes in goodwill:
		December 31,
		2013				2012
		(in millions)
	Beginning balance	$	156.4			$	155.9
	Foreign currency translation	—				0.5
	Ending balance	$	156.4			$	156.4

Restructuring_Actions_Restruct

Restructuring Actions Restructuring Actions (Tables)	12 Months Ended
	Dec. 31, 2013
Restructuring Actions [Abstract]	'
Schedule of Restructuring Reserve by Type of Cost [Table Text Block]	'
		One-time Termination Benefits			Asset Impairment Charges			Asset Retirement Obligations			Other Restructuring Actions			Total
		(in millions)
	Accrual as of January 1, 2012	$	0.3		$	—		$	0.6		$	—		$	0.9
	Charges	1.7			5.8			—			23.2			30.7
	Cash utilization	(1.6		)	—			(0.1		)	(23.2		)	(24.9		)
	Non-cash utilization	—			(5.8		)	—			—			(5.8		)
	Accrual adjustments	(0.4		)	—			—			—			(0.4		)
	Accrual as of December 31, 2012	$	—		$	—		$	0.5		$	—		$	0.5
	Charges	—			—			—			—			—
	Cash utilization	—			—			(0.3		)	—			(0.3		)
	Non-cash utilization	—			—			—			—			—
	Accrual adjustments	—			—			—			—			—
	Accrual as of December 31, 2013	$	—		$	—		$	0.2		$	—		$	0.2

LongTerm_Debt_LongTerm_Debt_Ta

Long-Term Debt Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2013
Long Term Debt and Lease Obligations [Abstract]	'
Schedule of Long-term Debt Instruments [Table Text Block]	'
	Long-term debt consists of the following:
		December 31,
		2013		2012
		(in millions)
	Amended Revolving Facility	$	—	$	—
	Term Facility	150		—
	9.25% Notes, net of discount	—		337.5
	7.875% Notes	—		300
	7.75% Notes	200		200
	6.625% Notes	550		550
	6.25% Notes	400		—
	5.125% Notes	200		—
	Foreign credit facilities	53.8		61
	Capital lease obligations	5.3		5.6
	Long-term debt	$	1,559.10	$	1,454.10
Schedule of Maturities of Long-term Debt [Table Text Block]	'
	2014	$	36.8
	2015	21.1
	2016	17.2
	2017	19.1
	2018	109.2
	Thereafter	1,355.70
	Total	$	1,559.10

Derivatives_Derivatives_Tables

Derivatives Derivatives (Tables)	12 Months Ended
	Dec. 31, 2013
Derivatives and Risk Management [Abstract]	'
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block]	'
	The following table summarizes the reclassification of pre-tax derivative gains (losses) into net income from accumulated other comprehensive income (loss):
		Location of Gain (Loss) Reclassified into Net Income	Gain (loss) Reclassified During the Twelve Months Ended December 31,					Gain Expected to be Reclassified During the Next 12 Months
			2013		2012
			(in millions)
	Currency forward contracts	Cost of Goods Sold	$	2.8	$	(1.8	)	$	0.3

Fair_Value_Fair_Value_Tables

Fair Value Fair Value (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value [Abstract]	'
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	'
		December 31, 2013						December 31, 2012
		Carrying Amount			Fair Value			Carrying Amount			Fair Value			Input
		(in millions)						(in millions)
	Balance Sheet Classification
	Cash equivalents	$	6.1		$	6.1		$	6.5		$	6.5		Level 1
	Prepaid expenses and other
	Currency forward contracts	0.7			0.7			2.3			2.3			Level 2
	Other accrued expenses
	Currency forward contracts	0.4			0.4			—			—			Level 2
Fair Value, Liabilities Measured on Recurring Basis [Table Text Block]	'
		December 31, 2013						December 31, 2012
		Carrying Amount			Fair Value			Carrying Amount			Fair Value			Input
		(in millions)						(in millions)
	Amended Revolving Facility	$	—		$	—		$	—		$	—		Level 2
	Term Facility	150			147.8			—			—			Level 2
	9.25% Notes	—			—			337.5			377.4			Level 2
	7.875% Notes	—			—			300			310.1			Level 2
	7.75% Notes	200			227.5			200			216.5			Level 2
	6.625% Notes	550			578.9			550			555.5			Level 2
	6.25% Notes	400			423			—			—			Level 2
	5.125% Notes	200			206			—			—			Level 2
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Table Text Block]	'
	The following table summarizes impairments of long-lived assets measured at fair value on a nonrecurring basis subsequent to initial recognition:
	Balance Sheet Classification		Fair Value Measurements using Level 3 Inputs			Asset Impairment Recorded in Twelve Months ended December 31, 2012			Fair Value Measurements using Level 3 Inputs			Asset Impairment Recorded in Twelve Months ended December 31, 2011
			(in millions)
	Property, plant and equipment, net		$	—		$	5.8		$	—		$	8.1
	Other assets and deferred charges		—			—			—			0.5
Fair Value - Impairment of Finite-lived Intangible Asset [Table Text Block]	'
	Balance Sheet Classification		Fair Value Measurement Using Level 3 Inputs			Impairment Recorded in the Twelve Months Ended December 31, 2011
			(in millions)
	Other assets and deferred charges		$	—		$	1.6

Employee_Benefit_Plans_Employe

Employee Benefit Plans Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2013
Employee Benefit Plans [Abstract]	'
Schedule of Assumptions Used [Table Text Block]	'
		Pension Benefits																		OPEB
		2013						2012						2011						2013			2012		2011
		U.S.			U.K			U.S.			U.K			U.S.			U.K.
	Discount rate	5	%		4.5	%		4.1	%		4.3	%		5.1	%		4.65	%		4.95	%		4.05	%	5.1	%
	Expected return on plan assets	7.5	%		5.15	%		7.5	%		4.35	%		8	%		4.6	%		N/A			N/A		N/A
	Rate of compensation increase	4	%		3.6	%		4	%		3.15	%		4	%		3.25	%		4	%		4	%	4	%
Change in Benefit Obligation and Plan Assets [Table Text Block]	'
		Pension Benefits								OPEB
		December 31,								December 31,
		2013				2012				2013				2012
		(in millions)								(in millions)
	Change in benefit obligation
	Benefit obligation at beginning of year	$	842.8			$	716.7			$	601.3			$	588.4
	Service cost	3.4				3.1				0.4				0.4
	Interest cost	33.8				35.1				13.2				15.1
	Plan amendments	—				6.1				(8.1		)		—
	Actuarial loss (gain)	(92.6		)		97.3				(0.7		)		(7.1		)
	Change in GM portion of OPEB obligation	—				—				(17.0		)		2.4
	Participant contributions	0.4				0.5				—				—
	Special and contractual termination benefits	—				12.8				—				18.3
	Settlements	—				—				—				(4.7		)
	Benefit payments	(35.3		)		(34.2		)		(11.2		)		(11.5		)
	Currency fluctuations	2.9				5.4				—				—
	Net change	(87.4		)		126.1				(23.4		)		12.9
	Benefit obligation at end of year	$	755.4			$	842.8			$	577.9			$	601.3
	Change in plan assets
	Fair value of plan assets at beginning of year	$	695.4			$	441.7			$	—			$	—
	Actual return on plan assets	49.2				57.3				—				—
	Employer contributions	0.8				225.4				11.2				11.5
	Participant contributions	0.4				0.5				—				—
	Benefit payments	(35.3		)		(34.2		)		(11.2		)		(11.5		)
	Currency fluctuations	2.9				4.7				—				—
	Net change	18				253.7				—				—
	Fair value of plan assets at end of year	$	713.4			$	695.4			$	—			$	—
Schedule of Amounts Recognized in Balance Sheet [Table Text Block]	'
		Pension Benefits								OPEB
		December 31,								December 31,
		2013				2012				2013				2012
		(in millions)								(in millions)
	Noncurrent assets	$	9.3			$	11.8			$	—			$	—
	Current liabilities	(2.3		)		(1.3		)		(30.8		)		(28.6		)
	Noncurrent liabilities	(49.0		)		(157.9		)		(547.1		)		(572.7		)
	Net liability	$	(42.0	)		$	(147.4	)		$	(577.9	)		$	(601.3	)
Schedule of Pre-tax Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]	'
		Pension Benefits								OPEB
		December 31,								December 31,
		2013				2012				2013				2012
		(in millions)								(in millions)
	Net actuarial gain (loss)	$	(194.3	)		$	(298.6	)		$	4.9			$	3.3
	Net prior service credit (cost)	0.8				(4.7		)		18.1				11.8
	Total amounts recorded	$	(193.5	)		$	(303.3	)		$	23			$	15.1
Schedule of Net Benefit Costs [Table Text Block]	'
		Pension Benefits												OPEB
		2013				2012				2011				2013				2012				2011
		(in millions)												(in millions)
	Service cost	$	3.4			$	3.1			$	4.8			$	0.4			$	0.4			$	0.9
	Interest cost	33.8				35.1				37.1				13.2				15.1				17.1
	Expected asset return	(45.8		)		(34.7		)		(31.9		)		—				—				—
	Amortized actuarial loss	8.9				7.8				4.5				0.9				0.6				0.4
	Amortized prior service cost (credit)	5.4				0.5				(0.1		)		(1.8		)		(2.0		)		(3.2		)
	Special and contractual
	termination benefits	—				12.8				—				—				16.2				—
	Curtailment gain	—				—				—				—				(21.8		)		—
	Settlement	—				—				0.1				—				(5.2		)		—
	Net periodic benefit cost	$	5.7			$	24.6			$	14.5			$	12.7			$	3.3			$	15.2
Schedule of Weighted Average Allocation of Pension Plan Assets [Table Text Block]	'
		U.S.								U.K.
								Target								Target
		2013			2012			Allocation		2013			2012			Allocation
	Equity securities	42.5	%		38.3	%		30% - 65%		30.7	%		34.8	%		25% - 35%
	Fixed income securities	48.5			52.3			35% - 55%		59			55.1			55% - 65%
	Hedge funds	8.8			8.5			0% - 15%		10.2			—			5% - 15%
	Cash	0.2			0.9			0% - 5%		0.1			10.1			0% - 10%
	Total	100	%		100	%				100	%		100	%
Schedule of Fair Value Hierarchy by Asset Category for Postretirement Benefit Plan Assets [Table Text Block]	'
	The fair values of our pension plan assets are as follows:
	December 31, 2013
	Asset Categories		Level 1				Level 2				Level 3				Total
			(in millions)
	Cash & Cash Equivalents		$	1.5			$	—			$	—			$	1.5
	Equity
	U.S. Large Cap		128				—				—				128
	U.S. Small/Mid Cap		49.4				—				—				49.4
	World Equity		109.3				—				—				109.3
	Fixed Income Securities
	Government & Agencies		70.5				63				—				133.5
	Corporate Bonds - Investment Grade		167.1				—				—				167.1
	Corporate Bonds - Non-investment Grade		25.8				—				—				25.8
	Emerging Market Debt		17.4				—				—				17.4
	Other		16.9				—				—				16.9
	Hedge Funds
	Property Funds		—				—				7.1				7.1
	Multi Strategy Hedge Fund		—				—				57.4				57.4
	Total Plan Assets		$	585.9			$	63			$	64.5			$	713.4
	December 31, 2012
	Asset Categories		Level 1				Level 2				Level 3				Total
			(in millions)
	Cash & Cash Equivalents		$	18.5			$	—			$	—			$	18.5
	Equity
	U.S. Large Cap		104				—				—				104
	U.S. Small/Mid Cap		46.9				—				—				46.9
	World Equity		111.2				—				—				111.2
	Fixed Income Securities
	Government & Agencies		100.4				—				—				100.4
	Corporate Bonds - Investment Grade		204.9				—				—				204.9
	Corporate Bonds - Non-investment Grade		26.4				—				—				26.4
	Emerging Market Debt		20.5				—				—				20.5
	Other		15				—				—				15
	Hedge Funds
	Multi Strategy Hedge Fund		—				—				47.6				47.6
	Total Plan Assets		$	647.8			$	—			$	47.6			$	695.4
Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block]	'
		December 31,
		2013				2012
		(in millions)
	Beginning balance	$	47.6			$	46.5
	Actual return on plan assets:
	Relating to assets still held at the reporting date	3.5				1.1
	Purchases, sales and settlements, net	13.4				—
	Ending balance	$	64.5			$	47.6

Stock_Based_Compensation_Stock

Stock Based Compensation Stock Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2013
Stock-based Compensation [Abstract]	'
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]	'
					Weighted-
		Number of			Average Exercise
		Shares			Price Per Share
		(in millions, except per share data)
	Outstanding at January 1, 2011	5			$	25.01
	Options granted	—			—
	Options exercised	(0.5	)		8.69
	Options canceled	(0.6	)		26.96
	Outstanding at December 31, 2011	3.9			$	26.95
	Options granted	0.2			9.19
	Options exercised	(0.1	)		2.81
	Options canceled	(1.0	)		25.12
	Outstanding at December 31, 2012	3			$	27.08
	Options granted	—			—
	Options exercised	(0.1	)		10.59
	Options canceled	(0.9	)		24.28
	Outstanding at December 31, 2013	2			$	29.22
	Exercisable at December 31, 2011	3.8			$	27.25
	Exercisable at December 31, 2012	2.8			$	28.02
	Exercisable at December 31, 2013	2			$	29.22
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]	'
						Weighted-				Weighted-
	Range of		Stock Options			Average Exercise		Weighted-Average	Stock Options	Average Exercise
	Exercise Prices		Outstanding			Price Per Share		Contractual Life	Exercisable	Price Per Share
			(in millions, except per share data)					(in years)	(in millions, except per share data)
	$9.19 - $15.58		0.4			$	13.35	3.9	0.4	$	13.35
	$19.54 - $26.65		0.6			26.07		2.3	0.6	26.07
	$33.71 - $40.83		1			38.53		0.1	1	38.53
			2			$	29.22	1.6	2	$	29.22
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	'
		2012
	Expected volatility	47		%
	Risk-free interest rate	1.17		%
	Dividend yield	—		%
	Expected life of options	6 years
	Weighted-average grant-date fair value	$	4.18
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]	'
					Weighted Average
		Number of			Grant Date Fair
		Shares/Units			Value per Share/Unit
		(in millions, except per share data)
	Outstanding at January 1, 2011	2.8			$	13.48
	Granted	—			—
	Vested	(1.1	)		17.41
	Canceled	(0.1	)		10.68
	Outstanding at December 31, 2011	1.6			$	10.74
	Granted	1			10.31
	Vested	(1.4	)		10.19
	Canceled	(0.1	)		26.02
	Outstanding at December 31, 2012	1.1			$	11.08
	Granted	0.9			12.79
	Vested	(0.7	)		11.06
	Canceled	—			—
	Outstanding at December 31, 2013	1.3			$	12.24

Income_Taxes_Income_Taxes_Tabl

Income Taxes Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Taxes [Abstract]	'
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]	'
		2013				2012				2011
		(in millions)
	U.S. income (loss)	$	(23.8	)		$	(6.0	)		$	20.3
	Non - U.S. income	110.1				37.5				117.8
	Total income before income taxes	$	86.3			$	31.5			$	138.1
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	'
		2013				2012				2011
		(in millions)
	Current
	Federal	$	(1.3	)		$	(3.3	)		$	(24.7	)
	Other state and local	0.1				1.1				(0.2		)
	Foreign	12.1				10.2				9.9
	Total current	$	10.9			$	8			$	(15.0	)
	Deferred
	Federal	$	(9.3	)		$	(347.1	)		$	22.3
	Other state and local	—				—				(1.4		)
	Foreign	(9.8		)		3.9				(4.9		)
	Total deferred	(19.1		)		(343.2		)		16
	Total income tax expense (benefit)	$	(8.2	)		$	(335.2	)		$	1
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	'
		2013			2012			2011
	Federal statutory	35	%		35	%		35	%
	Foreign income taxes	(48.5	)		(85.0	)		(34.6	)
	Change in enacted tax rate	(9.9	)		—			—
	State and local	0.2			3.5			(1.2	)
	Valuation allowance	12.4			(985.0	)		(30.7	)
	U.S. tax on unremitted foreign earnings	(0.2	)		(29.5	)		26.3
	Other	1.5			(3.2	)		5.9
	Effective income tax rate	(9.5	)%		(1,064.2	)%		0.7	%
Current Deferred Tax Assets and Liabilities [Table Text Block]	'
		December 31,
		2013				2012
		(in millions)
	Current deferred tax assets
	Employee benefits	$	14.5			$	16.9
	Inventory	8				12.6
	Prepaid taxes and other	24.6				15.5
	Valuation allowance	(10.7		)		(10.1		)
	Total current deferred tax assets	$	36.4			$	34.9
	Current deferred tax liabilities
	Unrealized foreign exchange gain and other	(0.1		)		(1.4		)
	Current deferred tax asset, net	$	36.3			$	33.5
Current Deferred Tax Assets and Liabilities, Net by Jurisdiction [Table Text Block]	'
		December 31,
		2013				2012
		(in millions)
	U.S. federal and state deferred tax asset, net	$	17.1			$	23
	Other foreign deferred tax asset, net	19.2				10.5
	Current deferred tax asset, net	$	36.3			$	33.5
Noncurrent Deferred Tax Assets and Liabilities [Table Text Block]	'
		December 31,
		2013				2012
		(in millions)
	Noncurrent deferred tax assets
	Employee benefits	$	161.5			$	200.7
	NOL carryforwards	176.9				177.4
	Tax credit carryforwards	82.9				79
	Capital allowance carryforwards	16				17.9
	Fixed assets	10.3				9
	Deferred revenue	15.7				20
	Capitalized expenditures	113.6				99.3
	Other	2.9				4
	Valuation allowances	(153.0		)		(156.0		)
	Noncurrent deferred tax assets	426.8				451.3
	Noncurrent deferred tax liabilities
	U.S. tax on unremitted foreign earnings	(85.0		)		(85.2		)
	Fixed assets and other	(9.8		)		(9.5		)
	Noncurrent deferred tax asset, net	$	332			$	356.6
Noncurrent Deferred Tax Assets and Liabilities, Net by Jurisdiction [Table Text Block]	'
		December 31,
		2013				2012
		(in millions)
	U.S. federal and state deferred tax asset, net	$	337.2			$	363.3
	Other foreign deferred tax asset (liability), net	(5.2		)		(6.7		)
	Noncurrent deferred tax asset, net	$	332			$	356.6
Schedule of Unrecognized Income Tax Benefits [Table Text Block]	'
		Unrecognized Income Tax				Interest and
		Benefits				Penalties
		(in millions)
	Balance at January 1, 2011	$	47.6			$	21.4
	Increase in prior year tax positions	—				1
	Decrease in prior year tax positions	(0.8		)		(2.3		)
	Increase in current year tax positions	1.3				—
	Settlement	(22.3		)		(12.7		)
	Balance at December 31, 2011	$	25.8			$	7.4
	Increase in prior year tax positions	—				2.8
	Decrease in prior year tax positions	(1.1		)		—
	Increase in current year tax positions	0.4				—
	Settlement	(4.4		)		—
	Balance at December 31, 2012	$	20.7			$	10.2
	Increase in prior year tax positions	6.1				0.1
	Decrease in prior year tax positions	(4.4		)		(6.2		)
	Increase in current year tax positions	4				—
	Settlement	(4.7		)		—
	Balance at December 31, 2013	$	21.7			$	4.1

Earnings_Per_Share_Earnings_Pe

Earnings Per Share Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings (Loss) per Share (EPS) [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	'
		2013		2012		2011
		(in millions, except per share data)
	Numerator
	Net income attributable to AAM	$	94.5	$	367.7	$	142.8
	Denominators
	Basic shares outstanding -
	Weighted-average shares outstanding	76.7		75.3		74.9
	Effect of dilutive securities -
	Dilutive stock options	0.1		0.1		0.1
	Dilutive warrants	—		—		0.4
	Diluted shares outstanding -
	Adjusted weighted-average shares after assumed conversions	76.8		75.4		75.4
	Basic EPS	$	1.23	$	4.88	$	1.91
	Diluted EPS	$	1.23	$	4.87	$	1.89

Commitments_and_Contingencies_

Commitments and Contingencies Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies [Abstract]	'
Schedule of Product Warranty Liability [Table Text Block]	'
		December 31,
		2013			2012
		(in millions)
	Beginning balance	$	29.1		$	13.4
	Accruals	12.8			23
	Settlements	(12.3		)	(0.9		)
	Adjustments to prior period accruals	(15.0		)	(6.4		)
	Foreign currency translation	(0.3		)	—
	Ending balance	$	14.3		$	29.1

Reclassifications_out_of_Accum1

Reclassifications out of Accumulated Other Comprehensive Income Reclassifications out of Accumulated Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]	'
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	'
	R

Segment_and_Geographic_Informa1

Segment and Geographic Information Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2013
Segment and Geographic Information [Abstract]	'
Schedule of Disclosure on Geographic Areas, Revenue and Long-Lived Assets by Country [Table Text Block]	'
		December 31,
		2013		2012		2011
		(in millions)
	Net sales
	United States	$	1,682.00	$	1,576.60	$	1,587.30
	Canada	74.4		75		60.8
	Mexico	865.6		755.1		678.5
	South America	201.1		216.4		134.8
	Asia	255.2		214.5		33.2
	Europe and other	129		93.3		90.4
	Total net sales	$	3,207.30	$	2,930.90	$	2,585.00
	Long-lived assets
	United States	$	850	$	865.3	$	845.7
	Mexico	469.3		417.7		384.9
	South America	100.2		113.3		131.9
	Asia	176.7		159		131.7
	Europe	93.2		72.5		51.3
	Total long-lived assets	$	1,689.40	$	1,627.80	$	1,545.50

Unaudited_Quarterly_Financial_1

Unaudited Quarterly Financial Data Unaudited Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2013
Unaudited Quarterly Financial Data [Abstract]	'
Schedule of Quarterly Financial Information [Table Text Block]	'
		Three Months Ended,
		31-Mar		30-Jun		30-Sep			31-Dec
		(in millions, except per share data)
	2013
	Net sales	$	755.6	$	799.6	$	820.8		$	831.3
	Gross profit	104.3		122.2		125.3			126.9
	Net income	7.3		25.8		31.6			29.8
	Net income attributable to AAM	7.3		25.8		31.6			29.8
	Basic EPS (1)	$	0.1	$	0.34	$	0.41		$	0.39
	Diluted EPS (1)	$	0.1	$	0.34	$	0.41		$	0.39
	2012
	Net sales	$	751.5	$	739.8	$	702.9		$	736.7
	Gross profit	139.2		85.8		90.7			84
	Net income (loss)	50.3		4.7		(8.2		)	319.9
	Net income (loss) attributable to AAM	51.2		4.7		(8.1		)	319.9
	Basic EPS (1)	$	0.68	$	0.06	$	(0.11	)	$	4.21
	Diluted EPS (1)	$	0.68	$	0.06	$	(0.11	)	$	4.21
	(1) Full year basic and diluted EPS will not necessarily agree to the sum of the four quarters because each quarter is a separate calculation.

Supplemental_Guarantor_Condens1

Supplemental Guarantor Condensed Consolidating Financial Statements Supplemental Guarantor Condensed Consolidating Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2013
Supplemental Guarantor Condensed Consolidating Financial Statements -9.25% Notes [Abstract]	'
Supplemental Guarantor Consolidating Income Statement [Table Text Block]	'
	Condensed Consolidating Statements of Income
	2013	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
		(in millions)
	Net sales
	External	$	—		$	773.6		$	226		$	2,207.70		$	—		$	3,207.30
	Intercompany	—			15.3			226.1			14			(255.4		)	—
	Total net sales	—			788.9			452.1			2,221.70			(255.4		)	3,207.30
	Cost of goods sold	—			769.4			389			1,825.60			(255.4		)	2,728.60
	Gross profit	—			19.5			63.1			396.1			—			478.7
	Selling, general and administrative expenses	—			182.4			0.1			55.9			—			238.4
	Operating income (loss)	—			(162.9		)	63			340.2			—			240.3
	Non-operating income (expense), net	—			(155.1		)	10.7			(9.6		)	—			(154.0		)
	Income (loss) before income taxes	—			(318.0		)	73.7			330.6			—			86.3
	Income tax expense (benefit)	—			(24.9		)	0.9			15.8			—			(8.2		)
	Earnings (loss) from equity in subsidiaries	94.5			167			(21.7		)	—			(239.8		)	—
	Net income (loss) before royalties and dividends	94.5			(126.1		)	51.1			314.8			(239.8		)	94.5
	Royalties and dividends	—			220.6			—			(220.6		)	—			—
	Net income after royalties and dividends	94.5			94.5			51.1			94.2			(239.8		)	94.5
	Net loss attributable to noncontrolling interests	—			—			—			—			—			—
	Net income attributable to AAM	$	94.5		$	94.5		$	51.1		$	94.2		$	(239.8	)	$	94.5
	Other comprehensive income (loss), net of tax	48.4			48.4			(7.2		)	(10.8		)	(30.4		)	48.4
	Comprehensive income attributable to AAM	$	142.9		$	142.9		$	43.9		$	83.4		$	(270.2	)	$	142.9
	2012	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Net sales
	External	$	—		$	704.8		$	214.4		$	2,011.70		$	—		$	2,930.90
	Intercompany	—			18.6			226.8			25.2			(270.6		)	—
	Total net sales	—			723.4			441.2			2,036.90			(270.6		)	2,930.90
	Cost of goods sold	—			709.8			389.8			1,702.20			(270.6		)	2,531.20
	Gross profit	—			13.6			51.4			334.7			—			399.7
	Selling, general and administrative expenses	—			186.5			—			56.8			—			243.3
	Operating income (loss)	—			(172.9		)	51.4			277.9			—			156.4
	Non-operating income (expense), net	—			(135.2		)	(2.2		)	12.5			—			(124.9		)
	Income (loss) before income taxes	—			(308.1		)	49.2			290.4			—			31.5
	Income tax expense (benefit)	—			(343.9		)	(5.5		)	14.2			—			(335.2		)
	Earnings (loss) from equity in subsidiaries	367.7			79			(49.2		)	—			(397.5		)	—
	Net income before royalties and dividends	367.7			114.8			5.5			276.2			(397.5		)	366.7
	Royalties and dividends	—			252.9			—			(252.9		)	—			—
	Net income after royalties and dividends	367.7			367.7			5.5			23.3			(397.5		)	366.7
	Net loss attributable to noncontrolling interests	—			—			—			1			—			1
	Net income attributable to AAM	$	367.7		$	367.7		$	5.5		$	24.3		$	(397.5	)	$	367.7
	Other comprehensive loss, net of tax	(60.5		)	(60.5		)	(10.1		)	(3.6		)	74.2			(60.5		)
	Foreign currency translation adjustments attributable to noncontrolling interests	0.3			0.3			—			0.3			(0.6		)	0.3
	Comprehensive income (loss) attributable to AAM	$	306.9		$	306.9		$	(4.6	)	$	20.4		$	(322.7	)	$	306.9
	2011	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Net sales
	External	$	—		$	777.7		$	195.3		$	1,612.00		$	—		$	2,585.00
	Intercompany	—			25.1			189.8			12.7			(227.6		)	—
	Total net sales	—			802.8			385.1			1,624.70			(227.6		)	2,585.00
	Cost of goods sold	—			727			334.2			1,296.30			(227.6		)	2,129.90
	Gross profit	—			75.8			50.9			328.4			—			455.1
	Selling, general and administrative expenses	—			192			—			39.7			—			231.7
	Operating income (loss)	—			(116.2		)	50.9			288.7			—			223.4
	Non-operating income (expense), net	—			(91.8		)	1			5.5			—			(85.3		)
	Income (loss) before income taxes	—			(208		)	51.9			294.2			—			138.1
	Income tax expense (benefit)	—			(5.2		)	1.2			5			—			1
	Earnings (loss) from equity in subsidiaries	142.8			165.5			(37.7		)	—			(270.6		)	—
	Net income (loss) before royalties and dividends	142.8			(37.3		)	13			289.2			(270.6		)	137.1
	Royalties and dividends	—			180.1			—			(180.1		)	—			—
	Net income after royalties and dividends	142.8			142.8			13			109.1			(270.6		)	137.1
	Net loss attributable to noncontrolling interests	—			—			—			5.7			—			5.7
	Net income attributable to AAM	$	142.8		$	142.8		$	13		$	114.8		$	(270.6	)	$	142.8
	Other comprehensive loss, net of tax	(97.6		)	(97.6		)	(29.0		)	(35.6		)	162.2			(97.6		)
	Foreign currency translation adjustments attributable to noncontrolling interests	0.2			0.2			—			0.2			(0.4		)	0.2
Comprehensive income (loss) attributable to AAM	$	45		$	45		$	(16.0	)	$	79		$	(108.0	)	$	45
Supplemental Guarantor Consolidating Balance Sheet [Table Text Block]	'
	Condensed Consolidating Balance Sheets
	2013	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Assets	(in millions)
	Current assets
	Cash and cash equivalents	$	—		$	36.9		$	—		$	117.1		$	—		$	154
	Accounts receivable, net	—			102.7			25.6			330.2			—			458.5
	Inventories, net	—			62.4			34.2			165.2			—			261.8
	Other current assets	—			43.8			3.2			76.5			—			123.5
	Total current assets	—			245.8			63			689			—			997.8
	Property, plant and equipment, net	—			239.8			83			735.7			—			1,058.50
	Goodwill	—			—			147.8			8.6			—			156.4
	Other assets and deferred charges	—			671.7			44.8			99.8			—			816.3
	Investment in subsidiaries	360.5			1,233.20			—			—			(1,593.7		)	—
	Total assets	$	360.5		$	2,390.50		$	338.6		$	1,533.10		$	(1,593.7	)	$	3,029.00
	Liabilities and stockholders' equity (deficit)
	Current liabilities
	Accounts payable	$	—		$	106.2		$	44.5		295.1			$	—		$	445.8
	Other current liabilities	—			120.4			4.1			96.8			—			221.3
	Total current liabilities	—			226.6			48.6			391.9			—			667.1
	Intercompany payable (receivable)	326.9			(390.1		)	(219.5		)	282.7			—			—
	Long-term debt	—			1,500.00			5.3			53.8			—			1,559.10
	Investment in subsidiaries obligation	—			—			15.2			—			(15.2		)	—
	Other long-term liabilities	—			693.5			0.5			75.2			—			769.2
	Total liabilities	326.9			2,030.00			(149.9		)	803.6			(15.2		)	2,995.40
	Total AAM Stockholders' equity	33.6			360.5			488.5			729.5			(1,578.5		)	33.6
	Noncontrolling interests in subsidiaries	—			—			—			—			—			—
	Total stockholders' equity	33.6			360.5			488.5			729.5			(1,578.5		)	33.6
	Total liabilities and stockholders' equity	$	360.5		$	2,390.50		$	338.6		$	1,533.10		$	(1,593.7	)	$	3,029.00
	2012	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Assets
	Current assets
	Cash and cash equivalents	$	—		$	10.6		$	—		$	51.8		$	—		$	62.4
	Accounts receivable, net	—			94.4			25.3			343.7			—			463.4
	Inventories, net	—			48.7			31.6			144			—			224.3
	Other current assets	—			48.8			3.5			69.7			—			122
	Total current assets	—			202.5			60.4			609.2			—			872.1
	Property, plant and equipment, net	—			250.4			84.2			675.1			—			1,009.70
	Goodwill	—			—			147.8			8.6			—			156.4
	Other assets and deferred charges	—			706.1			40			81.7			—			827.8
	Investment in subsidiaries	202.9			1,094.60			—			—			(1,297.5		)	—
	Total assets	$	202.9		$	2,253.60		$	332.4		$	1,374.60		$	(1,297.5	)	$	2,866.00
	Liabilities and stockholders' equity (deficit)
	Current liabilities
	Accounts payable	$	—		$	91.4		$	37.3		$	267.4		$	—		$	396.1
	Other current liabilities	—			124.5			3.8			76.4			—			204.7
	Total current liabilities	—			215.9			41.1			343.8			—			600.8
	Intercompany payable (receivable)	323.7			(420.6		)	(188.7		)	285.6			—			—
	Long-term debt	—			1,387.50			5.6			61			—			1,454.10
	Investment in subsidiaries obligation	—			—			7.6			—			(7.6		)	—
	Other long-term liabilities	—			867.9			1.2			62.8			—			931.9
	Total liabilities	323.7			2,050.70			(133.2		)	753.2			(7.6		)	2,986.80
	Total AAM Stockholders' equity (deficit)	(120.8		)	202.9			465.6			621.4			(1,289.9		)	(120.8		)
	Noncontrolling interests in subsidiaries	—			—			—			—			—			—
	Total stockholders' equity (deficit)	(120.8		)	202.9			465.6			621.4			(1,289.9		)	(120.8		)
	Total liabilities and stockholders' equity (deficit)	$	202.9		$	2,253.60		$	332.4		$	1,374.60		$	(1,297.5	)	$	2,866.00
Supplemental Guarantor Consolidating Statement of Cash Flows [Table Text Block]	'
	Condensed Consolidating Statements of Cash Flows
	2013	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
		(in millions)
	Net cash provided by (used in) operating activities	$	—		$	(70.4	)	$	84.9		$	208.5		$	—		$	223
	Investing activities
	Purchases of property, plant and equipment	—			(61.2		)	(12.5		)	(178.2		)	—			(251.9		)
	Proceeds from sale of property, plant and equipment	—			5.1			0.5			3.5			—			9.1
	Proceeds from sale-leaseback of equipment	—			24.1			—			—			—			24.1
	Net cash used in investing activities	—			(32.0		)	(12.0		)	(174.7		)	—			(218.7		)
	Financing activities
	Net debt activity	—			110.1			(0.3		)	(5.0		)	—			104.8
	Intercompany activity	0.4			34.1			(72.6		)	38.1			—			—
	Debt issuance costs	—			(16.6		)	—			(0.1		)	—			(16.7		)
	Employee stock option exercises	—			1.1			—			—			—			1.1
	Purchase of treasury stock	(0.4		)	—			—			—			—			(0.4		)
	Net cash provided by (used in) financing activities	—			128.7			(72.9		)	33			—			88.8
	Effect of exchange rate changes on cash	—			—			—			(1.5		)	—			(1.5		)
	Net increase in cash and cash equivalents	—			26.3			—			65.3			—			91.6
	Cash and cash equivalents at beginning of period	—			10.6			—			51.8			—			62.4
	Cash and cash equivalents at end of period	$	—		$	36.9		$	—		$	117.1		$	—		$	154
	2012	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Net cash provided by (used in) operating activities	$	—		$	(228.2	)	$	56.8		$	(4.1	)	$	—		$	(175.5	)
	Investing activities
	Purchases of property, plant and equipment	—			(59.4		)	(9.0		)	(139.2		)	—			(207.6		)
	Proceeds from sale of property, plant and equipment	—			7			—			3.1			—			10.1
	Proceeds from sale-leaseback of equipment	—			12.1			—			—			—			12.1
	Net cash used in investing activities	—			(40.3		)	(9.0		)	(136.1		)	—			(185.4		)
	Financing activities
	Net debt activity	—			257.9			(0.2		)	16.2			—			273.9
	Intercompany activity	5.9			(52.0		)	(47.6		)	93.7			—			—
	Debt issuance costs	—			(10.6		)	—			—			—			(10.6		)
	Employee stock option exercises	—			0.1			—			—			—			0.1
	Purchase of treasury stock	(5.9		)	—			—			—			—			(5.9		)
	Purchase of noncontrolling interest	—			—			—			(4.0		)	—			(4.0		)
	Net cash provided by (used in) financing activities	—			195.4			(47.8		)	105.9			—			253.5
	Effect of exchange rate changes on cash	—			—			—			0.6			—			0.6
	Net decrease in cash and cash equivalents	—			(73.1		)	—			(33.7		)	—			(106.8		)
	Cash and cash equivalents at beginning of period	—			83.7			—			85.5			—			169.2
	Cash and cash equivalents at end of period	$	—		$	10.6		$	—		$	51.8		$	—		$	62.4
	2011	Holdings			AAM Inc.			Guarantor Subsidiaries			Non-Guarantor Subsidiaries			Elims			Consolidated
	Net cash provided by (used in) operating activities	$	—		$	(119.3	)	$	40.1		$	22.9		$	—		$	(56.3	)
	Investing activities
	Purchases of property, plant and equipment	—			(43.9		)	(4.9		)	(114.3		)	—			(163.1		)
	Proceeds from sale of property, plant and equipment	—			1.5			—			7.4			—			8.9
	Acquisition, net	—			—			(16.5		)	—			—			(16.5		)
	Purchase buyouts of leased equipment	—			(13.4		)	—			—			—			(13.4		)
	Net cash used in investing activities	—			(55.8		)	(21.4		)	(106.9		)	—			(184.1		)
	Financing activities
	Net debt activity	—			159.6			(0.2		)	14.2			—			173.6
	Intercompany activity	0.1			37.9			(18.5		)	(19.5		)	—			—
	Debt issuance costs	—			(10.9		)	—			—			—			(10.9		)
	Employee stock option exercises, including tax benefit	—			4.6			—			—			—			4.6
	Purchase of treasury stock	(0.1		)	—			—			—			—			(0.1		)
	Net cash provided by (used in) financing activities	—			191.2			(18.7		)	(5.3		)	—			167.2
	Effect of exchange rate changes on cash	—			—			—			(2.2		)	—			(2.2		)
	Net increase (decrease) in cash and cash equivalents	—			16.1			—			(91.5		)	—			(75.4		)
	Cash and cash equivalents at beginning of period	—			67.6			—			177			—			244.6
	Cash and cash equivalents at end of period	$	—		$	83.7		$	—		$	85.5		$	—		$	169.2

Organization_and_Basis_of_Pres3

Organization and Basis of Presentation Revenue Recognition (Narrative) (Details) (USD $)

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Sep. 30, 2009

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2009

Dec. 31, 2008

Dec. 31, 2009

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

In Millions, unless otherwise specified

2009 GM Agreement [Member]

2009 GM Agreement [Member]

2009 GM Agreement [Member]

2009 GM Agreement [Member]

2008 GM Agreement [Member]

2008 GM Agreement [Member]

2008 GM Agreement [Member]

2008 GM Agreement [Member]

2008 GM Agreement [Member]

Miscellaneous Deferred Revenue [Member]

Miscellaneous Deferred Revenue [Member]

Miscellaneous Deferred Revenue [Member]

Deferred Revenue Arrangement [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2009 GM agreement, cash received

'

'

'

'

'

$110

'

'

'

'

'

'

'

'

2009 GM agreement, deferred revenue recognized

'

'

'

'

'

79.7

'

'

'

'

'

'

'

'

Deferred revenue

'

'

45.5

'

'

'

'

'

'

'

'

'

'

'

Deferred revenue, current

17

17.2

8

'

'

'

'

'

'

'

'

'

'

'

Deferred revenue, noncurrent

76.4

82.2

37.5

'

'

'

'

'

'

'

'

'

'

'

Deferred revenue, revenue recognized

'

'

8

8

8

'

9.5

57

'

'

'

10.5

13.1

15.6

2008 GM agreement, cash received in 2008

'

'

'

'

'

'

'

'

'

115

'

'

'

'

2008 GM agreement, cash received in 2009

'

'

'

'

'

'

'

'

60

'

'

'

'

'

2008 GM agreement, total deferred revenue recognized

'

'

'

'

'

'

'

'

'

'

213.7

'

'

'

2008 GM agreement, fair value of liability assumed by GM for postretirement cost sharing

'

'

'

'

'

'

'

'

'

'

$38.70

'

'

'

Organization_and_Basis_of_Pres4

Organization and Basis of Presentation Buydown Program (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Buydown Program [Line Items]	'	'
Buydown program expense	$2.30	$15

Organization_and_Basis_of_Pres5

Organization and Basis of Presentation Research and Development (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Research and development expense	$103.40	$123.40	$113.60

Organization_and_Basis_of_Pres6

Organization and Basis of Presentation Accounts Receivable (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'
Allowance for doubtful accounts	$4.90	$6.50

Organization_and_Basis_of_Pres7

Organization and Basis of Presentation Inventories (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Organization and Basis of Presentation [Abstract]	'	'
Raw materials and work-in-progress	$263.40	$220.30
Finished goods	25.7	25
Gross inventories	289.1	245.3
Inventory valuation reserves	-27.3	-21
Inventories, net	$261.80	$224.30

Organization_and_Basis_of_Pres8

Organization and Basis of Presentation Schedule of Property, Plant & Equipment (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'
Depreciation and tooling amortization	$151.80	$130.90	$123.70
Land	29.5	27.8	'
Land improvements	18.9	17.8	'
Buildings and building improvements	306.6	293.3	'
Machinery and equipment	1,648.60	1,512.60	'
Construction in progress	95.1	123.1	'
Property, plant and equipment, gross	2,098.70	1,974.60	'
Accumulated depreciation and amortization	-1,040.20	-964.9	'
Property, plant and equipment, net	$1,058.50	$1,009.70	'
Land Improvements [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Estimated Useful Lives	'10-15	'	'
Building and Building Improvements [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Estimated Useful Lives	' 15-40	'	'
Machinery and Equipment [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Estimated Useful Lives	' 3-12	'	'

Organization_and_Basis_of_Pres9

Organization and Basis of Presentation Goodwill Rollforward (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]	'	'
Beginning balance	$156.40	$155.90
Foreign currency translation	0	0.5
Ending balance	$156.40	$156.40

Recovered_Sheet1

Organization and Basis of Presentation Intangible Assets (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008
Acquired Finite-Lived Intangible Assets [Line Items]	'	'	'	'	'
Capitalized computer software, gross	$7.80	'	'	'	'
Capitalized computer software, amortization	0.1	'	'	'	'
Acquired finite-lived intangible asset, amount	'	'	'	8.7	9.6
Amortization of intangible assets	$1.90	$1.90	$1.90	'	'

Recovered_Sheet2

Organization and Basis of Presentation Impaired Intangible Assets (Narrative) (Details) (Change in Fair Value from Asset Impairment [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2011
Change in Fair Value from Asset Impairment [Member]	'
Impaired Intangible Assets [Line Items]	'
Impairment of intangible assets, finite-lived	$1.60

Recovered_Sheet3

Organization and Basis of Presentation Debt Issuance Costs (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'
Unamortized debt issuance costs	$35.60	$33

Restructuring_Actions_Restruct1

Restructuring Actions Restructuring Actions (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve, beginning balance	$0.50	$0.90
Charges	0	30.7
Cash utilization	-0.3	-24.9
Non-cash utilization	0	-5.8
Accrual adjustments	0	-0.4
Restructuring reserve, ending balance	0.2	0.5
One-time Termination Benefits [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve, beginning balance	0	0.3
Charges	0	1.7
Cash utilization	0	-1.6
Non-cash utilization	0	0
Accrual adjustments	0	-0.4
Restructuring reserve, ending balance	0	0
Asset Impairment Charges [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve, beginning balance	0	0
Cash utilization	0	0
Impairment of Long-Lived Assets to be Disposed of	0	5.8
Non-cash utilization	0	-5.8
Accrual adjustments	0	0
Restructuring reserve, ending balance	0	0
Environmental Restoration Costs [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve, beginning balance	0.5	0.6
Asset Retirement Obligation, Liabilities Incurred	0	0
Asset Retirement Obligation, Cash Paid to Settle	0.3	0.1
Non-cash utilization	0	0
Asset Retirement Obligation, Revision of Estimate	0	0
Restructuring reserve, ending balance	0.2	0.5
Other Restructuring [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Restructuring reserve, beginning balance	0	0
Charges	0	'
Cash utilization	0	-23.2
Non-cash utilization	0	0
Accrual adjustments	0	0
Restructuring reserve, ending balance	0	0
Other Restructuring Costs	'	$23.20

LongTerm_Debt_Longterm_Debt_In

Long-Term Debt Long-term Debt Instruments (Details) (USD $)

12 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

6 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 10, 2009

Dec. 31, 2013

Dec. 31, 2013

Mar. 01, 2013

Dec. 31, 2012

Feb. 27, 2007

Dec. 31, 2012

Dec. 31, 2013

Nov. 03, 2011

Dec. 31, 2013

Dec. 31, 2012

Sep. 17, 2012

Dec. 31, 2013

Sep. 18, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Jun. 30, 2013

Mar. 20, 2013

Dec. 31, 2013

Dec. 31, 2013

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Secured Debt [Member]

Secured Debt [Member]

Secured Debt [Member]

Secured Debt [Member]

Secured Debt [Member]

Secured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Foreign Credit Facilities [Member]

Foreign Credit Facilities [Member]

Capital Lease Obligations [Member]

Capital Lease Obligations [Member]

Class C [Member]

Class C [Member]

Debt Repurchase [Member]

Debt Redemption [Member]

Loans Payable [Member]

Loans Payable [Member]

9.25% Notes [Member]

9.25% Notes [Member]

9.25% Notes [Member]

9.25% Notes [Member]

7.875% Notes [Member]

7.875% Notes [Member]

7.875% Notes [Member]

7.875% Notes [Member]

7.875% Notes [Member]

7.75% Notes [Member]

7.75% Notes [Member]

7.75% Notes [Member]

6.625% Notes [Member]

6.625% Notes [Member]

6.625% Notes [Member]

5.25% Notes [Member]

5.25% Notes [Member]

6.25% Notes [Member]

6.25% Notes [Member]

5.125% Notes [Member]

5.125% Notes [Member]

Revolving Credit Facility [Member]

Revolving Credit Facility [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

7.875% Notes [Member]

7.875% Notes [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of credit facility, amount outstanding

'

'

'

$0

$0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$53,800,000

$61,000,000

'

'

'

'

'

'

Long-term debt

'

'

'

'

'

'

150,000,000

0

0

337,500,000

'

'

0

0

300,000,000

300,000,000

'

200,000,000

200,000,000

'

550,000,000

550,000,000

'

'

'

400,000,000

0

200,000,000

0

'

'

'

'

'

'

'

'

Capital lease obligations

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5,300,000

5,600,000

'

'

'

'

Long-term debt and capital lease obligations

1,559,100,000

1,454,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amended revolving facility, maximum borrowing capacity

'

'

'

523,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amended revolving facility, remaining borrowing capacity

'

'

'

501,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amended revolving facility, standby letters of credit issued against the facility

'

'

'

21,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Increase in Amended Revolving Facility aggregate commitments

'

'

'

158,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt issuance costs

16,700,000

10,600,000

10,900,000

6,900,000

1,700,000

5,900,000

'

'

'

'

'

'

'

'

'

'

'

5,000,000

'

'

0

'

'

'

'

6,600,000

'

3,100,000

'

'

'

'

'

'

'

'

'

Amended Revolving Facility, interest rate description

'Borrowings under the Amended Revolving Facility and Term Facility bear interest at rates based on adjusted LIBOR or an alternate base rate, plus an applicable margin. The applicable margin for LIBOR-based loans will be between 1.5% and 3.0%.

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Line of credit facility, reduction in borrowing capacity, termination of loan facility

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

72,800,000

'

'

Write off of deferred debt issuance cost

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

500,000

'

'

'

Debt instrument, face amount

'

'

'

'

'

'

'

'

'

'

'

425,000,000

'

'

'

'

300,000,000

'

'

200,000,000

'

'

550,000,000

'

250

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, interest rate, stated percentage

'

'

'

'

'

'

'

'

9.25%

'

'

'

7.88%

7.88%

'

'

'

'

7.75%

'

6.63%

'

'

0.00%

'

6.25%

'

5.13%

'

'

'

'

'

'

'

'

'

Debt instrument, original discount amount

'

'

'

'

'

'

'

'

'

'

'

5,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

9.25% Notes, percentage redeemed

'

'

'

'

'

'

'

'

'

10.00%

10.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

9.25% Notes, premium percentage applicable to voluntary redemption during the period

'

'

'

'

'

'

'

'

'

103.00%

103.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Repayments of long-term debt

652,000,000

299,100,000

56,000,000

'

'

'

'

'

340,000,000

42,500,000

42,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, early redemption premium

'

'

'

'

'

'

'

'

18,900,000

1,300,000

'

'

'

3,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt refinancing and redemption costs

36,800,000

19,800,000

3,100,000

'

'

'

'

'

6,700,000

1,000,000

1,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,200,000

900,000

Debt instrument, decrease, repayments

'

'

'

'

'

'

'

'

42,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, redemption amount

'

'

'

'

'

'

'

'

190,000,000

'

'

'

'

127,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, tender premium

'

'

'

'

'

'

'

'

'

'

'

'

5,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, tender offer, fees

'

'

'

'

'

'

'

'

'

'

'

'

'

100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, repurchased face amount

'

'

'

'

'

'

'

'

'

'

'

'

'

'

172,600,000

'

'

'

'

'

'

'

'

'

137,800,000

'

'

'

'

'

'

'

'

'

'

'

'

Foreign credit facilities, remaining borrowing capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

56,700,000

'

'

'

'

'

'

'

Interest expense

115,900,000

101,600,000

83,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Interest costs, capitalized during period

6,600,000

8,200,000

8,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long-term debt, weighted average interest rate

6.30%

7.90%

8.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

8.90%

'

'

'

'

'

Interest payable, current

19,900,000

35,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Investment income

600,000

600,000

1,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

9.25% Senior Secured Notes, Amount Paid for Redemption Premium During the Period

'

'

'

'

'

'

'

'

'

'

$1,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

LongTerm_Debt_Longterm_Debt_Ma

Long-Term Debt Long-term Debt Maturity Schedule (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'
2014	$36.80	'
2015	21.1	'
2016	17.2	'
2017	19.1	'
2018	109.2	'
Thereafter	1,355.70	'
Long-term debt	$1,559.10	$1,454.10

LongTerm_Debt_Leases_Narrative

Long-Term Debt Leases (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Proceeds from sale-leaseback of equipment	$24.10	$12.10	$0
Operating leases, future minimum payments due, current	19.6	'	'
Operating leases, future minimum payments, due in two years	17.4	'	'
Operating leases, future minimum payments, due in three years	15.5	'	'
Operating leases, future minimum payments, due in four years	13.6	'	'
Operating leases, future minimum payments, due in five years	6.8	'	'
Operating lease expense	17.6	9	6.8
Purchase of previously idled assets, reduction of cost of goods sold	'	0.5	'
Capital Lease Obligations [Member]	'	'	'
Capital leased assets, gross	6.7	6.7	'
Capital leases, balance sheet, assets by major class, net	$5.30	$5.60	'

Derivatives_Foreign_Currency_D

Derivatives Foreign Currency Derivatives (Narrative) (Details) (Forward Contracts [Member], USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Forward Contracts [Member]	'	'
Derivative [Line Items]	'	'
Derivative, notional amount	$67.20	$31.90

Derivatives_Derivatives_Detail

Derivatives Derivatives (Details) (Cost of Sales [Member], Cash Flow Hedging [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cost of Sales [Member] | Cash Flow Hedging [Member]	'	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'	'
Location of Gain (Loss) Reclassified into Net Income	'	'Cost of Goods Sold	'
Derivative instruments, gain (loss) reclassified from accumulated OCI into income, effective portion, net	'	$2.80	($1.80)
Gain Expected to be Reclassified During the Next 12 Months	$0.30	'	'

Derivatives_Sales_Receivables_

Derivatives Sales, Receivables and Postretirement Cost Sharing Asset by Major Customer (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue, Major Customer [Line Items]	'	'	'
Total GM postretirement cost sharing asset	$255.90	$273	'
General Motors [Member]	'	'	'
Revenue, Major Customer [Line Items]	'	'	'
Entity-wide revenue, major customer, percentage	71.00%	73.00%	73.00%
Fair value, concentration of risk, accounts receivable	278.5	325.8	'
Chrysler Group LLC [Member]	'	'	'
Revenue, Major Customer [Line Items]	'	'	'
Entity-wide revenue, major customer, percentage	12.00%	10.00%	8.00%
Fair value, concentration of risk, accounts receivable	$85.90	$43.50	'

Fair_Value_Fair_Value_of_Asset

Fair Value Fair Value of Assets and Liabilities Measured on Recurring and Nonrecurring Basis (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Reported Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash equivalents, at carrying value	$6.10	$6.50
Portion at Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Cash equivalents, fair value disclosure	6.1	6.5
Other Current Assets [Member] | Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Currency forward contracts, asset, fair value disclosure	0.7	2.3
Other Current Assets [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Currency forward contracts, asset, fair value disclosure	0.7	2.3
Accrued Liabilities [Member] | Reported Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Currency forward contracts, liability, fair value disclosure	0.4	0
Accrued Liabilities [Member] | Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Currency forward contracts, liability, fair value disclosure	$0.40	$0

Fair_Value_Fair_Value_of_Debt_

Fair Value Fair Value of Debt (Details) (Fair Value, Inputs, Level 2 [Member], USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Reported Value Measurement [Member] | Line of Credit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	$0	$0
Reported Value Measurement [Member] | Loans Payable [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	150	0
Reported Value Measurement [Member] | 9.25% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	0	337.5
Reported Value Measurement [Member] | 7.875% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	0	300
Reported Value Measurement [Member] | 7.75% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	200	200
Reported Value Measurement [Member] | 6.625% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	550	550
Reported Value Measurement [Member] | 6.25% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	400	0
Reported Value Measurement [Member] | 5.125% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	200	0
Estimate of Fair Value Measurement [Member] | Line of Credit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	0	0
Estimate of Fair Value Measurement [Member] | Loans Payable [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	147.8	0
Estimate of Fair Value Measurement [Member] | 9.25% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	0	377.4
Estimate of Fair Value Measurement [Member] | 7.875% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	0	310.1
Estimate of Fair Value Measurement [Member] | 7.75% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	227.5	216.5
Estimate of Fair Value Measurement [Member] | 6.625% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	578.9	555.5
Estimate of Fair Value Measurement [Member] | 6.25% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	423	0
Estimate of Fair Value Measurement [Member] | 5.125% Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Long-term debt	$206	$0

Fair_Value_Impairments_of_Long

Fair Value Impairments of Long-lived Assets Measured at Fair Value on a Nonrecurring Basis (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Asset impairment charges	$0	$5.80	$8.70
Payments to acquire equipment on lease	'	'	18.6
Loss on write-down of equipment	'	'	'5.3
Change in Fair Value from Asset Impairment [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Asset impairment charges	'	5.8	8.1
Asset impairment of other assets	'	0	0.5
Fair Value, Inputs, Level 3 [Member]	'	'	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'	'	'
Property, plant, and equipment, fair value disclosure	'	0	0
Other assets, fair value disclosure	'	$0	$0

Fair_Value_Impairment_of_Indef

Fair Value Impairment of Indefinite-lived Intangible Assets Measured at Fair Value on a Nonrecurring Basis (Details) (Change in Fair Value from Asset Impairment [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2011
Change in Fair Value from Asset Impairment [Member]	'
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]	'
Impairment of intangible assets, finite-lived	$1.60

Employee_Benefit_Plans_Defined

Employee Benefit Plans Defined Benefit Plan, Assumptions Used (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other Postretirement Benefit Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Discount rate	4.95%	4.05%	5.10%
Rate of compensation increase	4.00%	4.00%	4.00%
United States Pension Plan of US Entity, Defined Benefit [Member]	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Discount rate	5.00%	4.10%	5.10%
Expected return on plan assets	7.50%	7.50%	8.00%
Rate of compensation increase	4.00%	4.00%	4.00%
Foreign Pension Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Discount rate	4.50%	4.30%	4.65%
Expected return on plan assets	5.15%	4.35%	4.60%
Rate of compensation increase	3.60%	3.15%	3.25%

Employee_Benefit_Plans_Change_

Employee Benefit Plans Change in Benefit Obligation and Plan Assets (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Defined benefit plan, pension plans with accumulated benefit obligations in excess of plan assets, aggregate accumulated benefit obligation	$612.60	'	'
Defined benefit plan, pension plans with accumulated benefit obligations in excess of plan assets, aggregate projected benefit obligation	621.3	'	'
Defined benefit plan, pension plans with accumulated benefit obligations in excess of plan assets, aggregate fair value of plan assets	570.1	'	'
Special and contractual termination benefits	'	28.7	'
Fair value of plan assets at beginning of year	695.4	'	'
Fair value of plan assets at end of year	713.4	695.4	'
Pension Contributions in Excess of Statutory Minimums	114.7	'	'
Pension Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Service cost	3.4	3.1	4.8
Interest cost	33.8	35.1	37.1
Plan amendments	'	6.1	'
Special and contractual termination benefits	0	12.8	0
Other Postretirement Benefit Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Service cost	0.4	0.4	0.9
Interest cost	13.2	15.1	17.1
Special and contractual termination benefits	0	16.2	0
Settlements	'	4.7	'
Change in Benefit Obligation [Member] | Pension Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Benefit obligation at beginning of year	842.8	716.7	'
Service cost	3.4	3.1	'
Interest cost	33.8	35.1	'
Plan amendments	0	6.1	'
Actuarial loss (gain)	-92.6	97.3	'
Change in GM portion of OPEB obligation	0	0	'
Participant contributions	0.4	0.5	'
Special and contractual termination benefits	0	12.8	'
Settlements	0	0	'
Benefit payments	-35.3	-34.2	'
Currency fluctuations	2.9	5.4	'
Net change	-87.4	126.1	'
Benefit obligation at end of year	755.4	842.8	'
Benefit payments	-35.3	-34.2	'
Change in Benefit Obligation [Member] | Other Postretirement Benefit Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Benefit obligation at beginning of year	601.3	588.4	'
Service cost	0.4	0.4	'
Interest cost	13.2	15.1	'
Plan amendments	-8.1	0	'
Actuarial loss (gain)	-0.7	-7.1	'
Change in GM portion of OPEB obligation	-17	2.4	'
Participant contributions	0	0	'
Special and contractual termination benefits	0	18.3	'
Settlements	0	-4.7	'
Benefit payments	-11.2	-11.5	'
Currency fluctuations	0	0	'
Net change	-23.4	12.9	'
Benefit obligation at end of year	577.9	601.3	'
Benefit payments	-11.2	-11.5	'
Change in Plan Assets [Member] | Pension Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Participant contributions	0.4	0.5	'
Benefit payments	-35.3	-34.2	'
Fair value of plan assets at beginning of year	695.4	441.7	'
Actual return on plan assets	49.2	57.3	'
Employer contributions	0.8	225.4	'
Benefit payments	-35.3	-34.2	'
Currency fluctuations	2.9	4.7	'
Net change	18	253.7	'
Fair value of plan assets at end of year	713.4	695.4	'
Change in Plan Assets [Member] | Other Postretirement Benefit Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Participant contributions	0	0	'
Benefit payments	-11.2	-11.5	'
Fair value of plan assets at beginning of year	0	0	'
Actual return on plan assets	0	0	'
Employer contributions	11.2	11.5	'
Benefit payments	-11.2	-11.5	'
Currency fluctuations	0	0	'
Net change	0	0	'
Fair value of plan assets at end of year	$0	$0	'

Employee_Benefit_Plans_Amounts

Employee Benefit Plans Amounts Recognized in the Balance Sheet (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Change in postretirement benefit obligation due to remeasurement of the plan	'	$16.40	'
Defined benefit plan, effect of one percentage point decrease on accumulated postretirement benefit obligation	28.1	'	'
Defined benefit plan, effect of one percentage point increase on accumulated postretirement benefit obligation	33.6	'	'
GM postretirement cost sharing asset, current	13.9	'	'
GM postretirement cost sharing asset, noncurrent	242	'	259.7
Total GM postretirement cost sharing asset	255.9	'	273
Impact on accumulated other comprehensive income (loss) due to plan remeasurement	'	13.7	'
Pension Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Noncurrent assets	9.3	'	11.8
Defined benefit pension plan liabilities, current	-2.3	'	-1.3
Defined benefit pension plan, liabilities, noncurrent	-49	'	-157.9
Defined benefit plan, amounts recognized in balance sheet	-42	'	-147.4
Other Postretirement Benefit Plan, Defined Benefit [Member]	'	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'	'
Noncurrent assets	0	'	0
Postemployment benefits liability, current	-30.8	'	-28.6
Other postretirement defined benefit plan, liabilities, noncurrent	-547.1	'	-572.7
Other postretirement defined benefit plan, liabilities	($577.90)	'	($601.30)

Employee_Benefit_Plans_Pretax_

Employee Benefit Plans Pre-tax Amounts Recorded in AOCI (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'
Impact on accumulated other comprehensive income (loss), curtailment gain (loss)	$21.80	'
Pension Plan, Defined Benefit [Member]	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'
Net actuarial gain (loss)	-298.6	-194.3
Net prior service credit (cost)	-4.7	0.8
Total amounts recorded	-303.3	-193.5
Other Postretirement Benefit Plan, Defined Benefit [Member]	'	'
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]	'	'
Net actuarial gain (loss)	3.3	4.9
Net prior service credit (cost)	11.8	18.1
Total amounts recorded	15.1	23
Pension and other postretirement benefits, reduction in accumulated other comprehensive loss due to settlement gain	$0.50	'

Employee_Benefit_Plans_Compone

Employee Benefit Plans Components of Net Periodic Benefit Cost (Credit) (Details) (USD $)

12 Months Ended

In Millions, unless otherwise specified

Dec. 31, 2019

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Pension Plan, Defined Benefit [Member]

Pension Plan, Defined Benefit [Member]

Pension Plan, Defined Benefit [Member]

Pension Plan, Defined Benefit [Member]

Other Postretirement Benefit Plan, Defined Benefit [Member]

Other Postretirement Benefit Plan, Defined Benefit [Member]

Other Postretirement Benefit Plan, Defined Benefit [Member]

Other Postretirement Benefit Plan, Defined Benefit [Member]

Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Service cost

'

'

'

'

'

$3.40

$3.10

$4.80

'

$0.40

$0.40

$0.90

Interest cost

'

'

'

'

'

33.8

35.1

37.1

'

13.2

15.1

17.1

Expected asset return

'

'

'

'

'

-45.8

-34.7

-31.9

'

0

0

0

Amortized actuarial loss

'

'

'

'

'

8.9

7.8

4.5

'

0.9

0.6

0.4

Amortized prior service cost (credit)

'

'

'

'

'

5.4

0.5

-0.1

'

-1.8

-2

-3.2

Special and contractual termination benefits

'

'

'

28.7

'

0

12.8

0

'

0

16.2

0

Curtailment gain

'

'

'

'

'

0

0

0

'

0

-21.8

0

Settlement

'

'

'

'

'

0

0

0.1

'

0

-5.2

0

Net periodic benefit cost

'

'

'

'

'

5.7

24.6

14.5

'

'

'

'

Other postretirement benefit expense

'

'

'

'

'

'

'

'

'

12.7

3.3

15.2

Defined benefit plan, acceleration of prior service cost due to remeasurement

'

'

4.7

'

'

'

'

'

'

'

'

'

Pension and OPEB, period expense, other

'

'

28.7

'

'

'

'

'

'

'

'

'

Defined benefit plan, amortization of net gains (losses)

'

'

'

'

5.5

'

'

'

0.5

'

'

'

Defined benefit plan, amortization of net prior service cost (credit)

'

'

'

'

0.1

'

'

'

2.7

'

'

'

Defined benefit plan, health care cost trend rate assumed for next fiscal year

'

7.50%

'

'

'

'

'

'

'

'

'

'

Defined benefit plan, ultimate health care cost trend rate

5.00%

'

'

'

'

'

'

'

'

'

'

'

Defined benefit plan, year that rate reaches ultimate trend rate

'2019

'

'

'

'

'

'

'

'

'

'

'

Defined benefit plan, effect of one percentage point increase on service and interest cost components

'

'

1.6

'

'

'

'

'

'

'

'

'

Defined benefit plan, effect of one percentage point decrease on service and interest cost components

'

'

$1.40

'

'

'

'

'

'

'

'

'

Employee_Benefit_Plans_Pension

Employee Benefit Plans Pension Plan Assets by Category (Details)	Dec. 31, 2013	Dec. 31, 2012
United States Pension Plan of US Entity, Defined Benefit [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	100.00%	100.00%
United States Pension Plan of US Entity, Defined Benefit [Member] | Equity Securities [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	42.50%	38.30%
United States Pension Plan of US Entity, Defined Benefit [Member] | Fixed Income Funds [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	48.50%	52.30%
United States Pension Plan of US Entity, Defined Benefit [Member] | Hedge Funds [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	8.80%	8.50%
United States Pension Plan of US Entity, Defined Benefit [Member] | Cash and Cash Equivalents [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	0.20%	0.90%
Foreign Pension Plan, Defined Benefit [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	100.00%	100.00%
Foreign Pension Plan, Defined Benefit [Member] | Equity Securities [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	30.70%	34.80%
Foreign Pension Plan, Defined Benefit [Member] | Fixed Income Funds [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	59.00%	55.10%
Foreign Pension Plan, Defined Benefit [Member] | Hedge Funds [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	10.20%	0.00%
Foreign Pension Plan, Defined Benefit [Member] | Cash and Cash Equivalents [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Actual Plan Asset Allocations	0.10%	10.10%

Employee_Benefit_Plans_OPEB_Pl

Employee Benefit Plans OPEB Plan Assets by Category and Fair Value Hierarchy (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	$713.40	$695.40
Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	585.9	647.8
Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	63	0
Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	64.5	47.6
Cash and Cash Equivalents [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	1.5	18.5
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	1.5	18.5
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
U.S. Large Cap [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	128	104
U.S. Large Cap [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	128	104
U.S. Large Cap [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
U.S. Large Cap [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
U.S. Small/Mid Cap [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	49.4	46.9
U.S. Small/Mid Cap [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	49.4	46.9
U.S. Small/Mid Cap [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
U.S. Small/Mid Cap [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Equity Securities, Other [Member] (Deprecated 2013-01-31)	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	109.3	111.2
Equity Securities, Other [Member] (Deprecated 2013-01-31) | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	109.3	111.2
Equity Securities, Other [Member] (Deprecated 2013-01-31) | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Equity Securities, Other [Member] (Deprecated 2013-01-31) | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Government Agencies [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	133.5	100.4
Government Agencies [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	70.5	100.4
Government Agencies [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	63	0
Government Agencies [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Investment Grade Corporate Bonds [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	167.1	204.9
Investment Grade Corporate Bonds [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	167.1	204.9
Investment Grade Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Investment Grade Corporate Bonds [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
NonInvestment Grade Corporate Bonds [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	25.8	26.4
NonInvestment Grade Corporate Bonds [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	25.8	26.4
NonInvestment Grade Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
NonInvestment Grade Corporate Bonds [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Emerging Market Debt [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	17.4	20.5
Emerging Market Debt [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	17.4	20.5
Emerging Market Debt [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Emerging Market Debt [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Fixed Income Securities [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	16.9	15
Fixed Income Securities [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	16.9	15
Fixed Income Securities [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Fixed Income Securities [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Hedge Funds, Multi-strategy [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	57.4	47.6
Hedge Funds, Multi-strategy [Member] | Fair Value, Inputs, Level 1 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Hedge Funds, Multi-strategy [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	0	0
Hedge Funds, Multi-strategy [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	57.4	47.6
Commercial Real Estate [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	7.1	'
Commercial Real Estate [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Fair value of plan assets	$7.10	'

Employee_Benefit_Plans_Change_1

Employee Benefit Plans Change in Fair Value of Level 3 OPEB Assets (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset value	$64.50	$47.60	$46.50
Defined Benefit Plan, Actual Return on Plan Assets [Abstract]	'	'	'
Relating to assets still held at the reporting date	3.5	1.1	'
Purchases, sales and settlements, net	$13.40	$0	'

Employee_Benefit_Plans_Accumul

Employee Benefit Plans Accumulated Benefit Obligation (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Defined Benefit Plan Disclosure [Line Items]	'	'
Defined benefit plan, accumulated benefit obligation	$744.50	$828.40

Employee_Benefit_Plans_Expecte

Employee Benefit Plans Expected Future Pension and Other Postretirement Payments (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2014
In Millions, unless otherwise specified		Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]	'	'
Defined benefit plan, estimated future employer contributions in next fiscal year	'	$17
Defined benefit plan, expected future benefit payments in year one	55.9	'
Defined benefit plan, expected future benefit payments in year two	57.3	'
Defined benefit plan, expected future benefit payments in year three	57.8	'
Defined benefit plan, expected future benefit payments in year four	59	'
Defined benefit plan, expected future benefit payments in year five	59.4	'
Defined benefit plan, expected future benefit payments in five fiscal years thereafter	$309.20	'

Employee_Benefit_Plans_Defined1

Employee Benefit Plans Defined Contribution Plans (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Salaried Savings Plan [Member]	'	'	'
Defined contribution plans, maximum company match, salaried voluntary savings plan	50.00%	'	'
Defined contribution plans, ARC, range of percentage of salary eligible for contribution, low end of range	10.00%	'	'
Defined contribution plans, salaried voluntary savings plan, matching contributions during the period	$3.90	$3.30	$3.20
Annual Retirement Contribution (ARC) [Member]	'	'	'
Defined contribution plans, ARC, range of percentage of salary eligible for contribution, low end of range	5.00%	'	'
Defined contribution plan, employer matching contribution, percent	3.00%	'	'
Defined contribution plans, ARC, contributions made during period	4.6	4.4	3.6
Defined contribution plans, ARC, hourly associates, contributions made during period	1.9	1.6	1.9
Hourly Voluntary Savings Plan [Member]	'	'	'
Defined contribution plans, ARC, range of percentage of salary eligible for contribution, low end of range	6.00%	'	'
Defined contribution plan, maximum annual contribution per employee, amount	25.00%	'	'
Defined contribution plans, hourly voluntary savings plan, matching contributions during the period	$0.10	$0.10	$0.20

Employee_Benefit_Plans_Deferre

Employee Benefit Plans Deferred Compensation Plan (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Sep. 30, 2013
				Board of Directors Chairman [Member]	Board of Directors Chairman [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]	'	'	'	'	'
Deferred compensation distributions	$6.10	$0.80	$1.10	'	'
Deferred compensation arrangement with individual, distributions paid	'	'	'	'	5.6
Increase (decrease) in deferred compensation	-0.8	-1.3	-0.3	5.6	'
Proceeds from life insurance policies	'	'	'	5	'
Deferred compensation arrangement with individuals, recorded liability	$6.20	$11.30	'	'	'

Stock_Based_Compensation_Stock1

Stock Based Compensation Stock Based Compensation (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Share-based compensation arrangement by share-based payment award, number of shares authorized	18.5	'	'	'
Share-based compensation arrangement by share-based payment award, number of shares available for grant	2.9	'	'	'
Share-based compensation arrangement by share-based payment award, award vesting period	'10 years	'	'	'
Options outstanding	3	3.9	5	'
Options granted	0	0.2	0	'
Options exercised	-0.1	-0.1	-0.5	'
Options canceled	-0.9	-1	-0.6	'
Options outstanding	2	3	3.9	'
Weighted-average price outstanding	$29.22	$27.08	$26.95	$25.01
Weighted-average price granted	$0	$9.19	$0	'
Weighted-average price exercised	$10.59	$2.81	$8.69	'
Weighted-average price canceled	$24.28	$25.12	$26.96	'
Options exercisable	2	2.8	3.8	'
Weighted-average price of options exercisable	$29.22	$28.02	$27.25	'
Share-based compensation arrangement by share-based payment award, options, outstanding, intrinsic value	$3.20	'	'	'
Share-based compensation arrangement by share-based payment award, options, exercises in period, total intrinsic value	0.8	0.5	3	'
Share-based compensation arrangement by share-based payment award, options, exercisable, intrinsic value	$3.20	'	'	'

Stock_Based_Compensation_Stock2

Stock Based Compensation Stock Options - Range of Exercise Prices (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock Options Outstanding	2	'	'	'
Weighted-average Exercise Price Per Share	$29.22	$27.08	$26.95	$25.01
Weighted-average Contractual Life	'1 year 220 days	'	'	'
Stock Options Exercisable	2	'	'	'
Weighted-average Exercise Price Per Share	$29.22	$28.02	$27.25	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Range of Exercise Prices, $9.19-$15.58 [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock Options Outstanding	0.4	'	'	'
Weighted-average Exercise Price Per Share	$13.35	'	'	'
Weighted-average Contractual Life	'3 years 329 days	'	'	'
Stock Options Exercisable	0.4	'	'	'
Weighted-average Exercise Price Per Share	$13.35	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Range of Exercise Prices, $19.54-$26.65 [Member] [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock Options Outstanding	0.6	'	'	'
Weighted-average Exercise Price Per Share	$26.07	'	'	'
Weighted-average Contractual Life	'2 years 110 days	'	'	'
Stock Options Exercisable	0.6	'	'	'
Weighted-average Exercise Price Per Share	$26.07	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Options, Range of Exercise Prices,$33.71-$40.83 [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Stock Options Outstanding	1	'	'	'
Weighted-average Exercise Price Per Share	$38.53	'	'	'
Weighted-average Contractual Life	'0 years 36 days	'	'	'
Stock Options Exercisable	1	'	'	'
Weighted-average Exercise Price Per Share	$38.53	'	'	'

Stock_Based_Compensation_Fair_

Stock Based Compensation Fair Value Assumptions, Stock Options Granted (Details) (USD $)	12 Months Ended
	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Expected volatility	47.00%
Risk-free interest rate	1.17%
Dividend yield	0.00%
Expected life of options	'6 years
Weighted-average grant-date fair value	$4.18

Stock_Based_Compensation_Stock3

Stock Based Compensation Stock Based Payment Awards - Equity Instruments Other Than Options (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Restricted stock units outstanding	1.1	1.6	2.8	'
Restricted stock units granted	0.9	1	0	'
Restricted stock units vested	-0.7	-1.4	-1.1	'
Restricted stock units canceled	0	-0.1	-0.1	'
Restricted stock units outstanding	1.3	1.1	1.6	'
Weighted-average grant date fair value outstanding	$12.24	$11.08	$10.74	$13.48
Weighted-average grant date fair value granted	$12.79	$10.31	$0	'
Weighted-average grant date fair value vested	$11.06	$10.19	$17.41	'
Weighted-average grant date fair value canceled	$0	$26.02	$10.68	'
Share-based compensation arrangement by share-based payment award, equity instruments other than options, vested in period, total fair value	$13.80	$17.60	'	'
Share-based compensation arrangement by share-based payment award, equity instruments other than options, total share-based liabilities paid	'	0.2	0.4	'
Restricted Stock Units (RSUs) [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, share-based awards other than options	$8	'	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition	'2 years	'	'	'
Performance Awards [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition	'12 months	'	'	'

Stock_Based_Compensation_Perfo

Stock Based Compensation Performance Awards (Narrative) (Details) (Performance Awards [Member], USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Performance Awards [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Stock or unit option plan expense	$7.90	$3	$3.50
Performance awards, liability at period end	10.8	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized	$1.20	'	'
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition	'12 months	'	'

Income_Taxes_Income_Loss_Befor

Income Taxes Income (Loss) Before Income Taxes (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
U.S. income (loss)	($23.80)	($6)	$20.30
Non-U.S. income	110.1	37.5	117.8
Income before income taxes	$86.30	$31.50	$138.10

Income_Taxes_Components_of_Pro

Income Taxes Components of Provision for Income Taxes (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current	'	'	'
Federal	($1.30)	($3.30)	($24.70)
Other state and local	0.1	1.1	-0.2
Foreign	12.1	10.2	9.9
Total current	10.9	8	-15
Deferred	'	'	'
Federal	-9.3	-347.1	22.3
Other state and local	0	0	-1.4
Foreign	-9.8	3.9	-4.9
Total deferred	-19.1	-343.2	16
Income tax expense (benefit)	-8.2	-335.2	1
Income tax expense (benefit), continuing operations, adjustment of deferred tax (asset) liability	8.5	'	'
Income tax expense (benefit), change in estimate	4.8	'	'
Income tax expense (benefit), other	-3.3	'	'
Release of valuation allowance on net federal deferred tax assets in the U.S.	'	337.5	'
Net tax expense from amendment of state tax returns due to settlement of federal income tax audits	$1.30	'	'

Income_Taxes_Rate_Reconciliati

Income Taxes Rate Reconciliation (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Effective income tax rate reconciliation, Federal statutory	35.00%	35.00%	35.00%
Effective income tax rate reconciliation, foreign income taxes	-48.50%	-85.00%	-34.60%
Effective income tax rate reconciliation, change in enacted tax rate	-9.90%	0.00%	0.00%
Effective income tax rate reconciliation, State and local	0.20%	3.50%	-1.20%
Effective income tax rate reconciliation, valuation allowance	12.40%	-985.00%	-30.70%
Effective income tax rate reconciliation, U.S. tax on unremitted foreign earnings	-0.20%	-29.50%	26.30%
Effective income tax rate reconciliation, other	1.50%	-3.20%	5.90%
Effective income tax rate	-9.50%	-1064.20%	0.70%
2011 net tax benefit from audit settlements and reversal of State DTL's	'	$4.50	'
Previously enacted tax rate	17.50%	'	'
Newly enacted tax rate	30.00%	'	'

Income_Taxes_Components_of_Cur

Income Taxes Components of Current Deferred Tax Assets and Liabilities (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Total current deferred tax assets	$36.40	$34.90
Unrealized foreign exchange gain and other	-0.1	-1.4
Current deferred tax asset, net	36.3	33.5
NOL and tax credit carryforward, range of carryforward period, lower end of range	'5 years	'
NOL and tax credit carryforward, range of carryforward period, upper end of range	'20 years	'
Deferred Tax Assets, Current [Member]	'	'
Employee benefits	14.5	16.9
Inventory	8	12.6
Prepaid taxes and other	24.6	15.5
Valuation allowance	-10.7	-10.1
Total current deferred tax assets	$36.40	$34.90

Income_Taxes_Current_Deferred_

Income Taxes Current Deferred Tax Assets and Liabilities Recognized in Balance Sheet (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Current deferred tax asset, net	$36.30	$33.50
Domestic [Member]	'	'
Current deferred tax asset, net	17.1	23
Foreign [Member]	'	'
Current deferred tax asset, net	$19.20	$10.50

Income_Taxes_Components_of_Non

Income Taxes Components of Noncurrent Deferred Tax Assets and Liabilities (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Noncurrent deferred tax assets	$341.80	$366.10
U.S. tax on unremitted foreign earnings	-85	-85.2
Fixed assets and other	-9.8	-9.5
Noncurrent deferred tax asset, net	332	356.6
Deferred Tax Assets, Noncurrent [Member]	'	'
Employee benefits	161.5	200.7
NOL carryforwards	176.9	177.4
Tax credit carryforward	82.9	79
Capital allowance carryforward	16	17.9
Fixed assets	10.3	9
Deferred revenue	15.7	20
Capitalized expenditures	113.6	99.3
Other	2.9	4
Valuation allowances	-153	-156
Noncurrent deferred tax assets	426.8	451.3
Deferred Tax Assets, Current [Member]	'	'
Employee benefits	14.5	16.9
Other	$24.60	$15.50

Income_Taxes_Noncurrent_Deferr

Income Taxes Noncurrent Deferred Tax Assets and Liabilities Recognized in the Balance Sheet (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Deferred tax assets (liabilities), net, noncurrent	$332	$356.60
Deferred tax assets, operating loss and tax credit carryforwards	275.8	274.3
Deferred tax assets, operating loss and tax credit carryforwards, not subject to expiration	74.5	'
Foreign [Member]	'	'
Deferred tax assets (liabilities), net, noncurrent	-5.2	-6.7
Domestic [Member]	'	'
Deferred tax assets (liabilities), net, noncurrent	$337.20	$363.30

Income_Taxes_Unrecognized_Tax_

Income Taxes Unrecognized Tax Benefts (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Contingency [Line Items]	'	'	'
Unrecognized tax benefits, beginning balance	$20.70	$25.80	$47.60
Increase in prior year tax positions	6.1	0	0
Decrease in prior year tax positions	-4.4	-1.1	-0.8
Increase in current year tax positions	4	0.4	1.3
Settlement	-4.7	-4.4	-22
Unrecognized tax benefits, ending balance	21.7	20.7	25.8
Unrecognized tax benefits, interest and penalties, beginning balance	10.2	7.4	21.4
Interest and penalties, increase in prior year tax positions	0.1	2.8	1
Interest and penalties, decrease in prior year tax positions	-6.2	0	-2.3
Interest and penalties, increase in current year tax positions	0	0	0
Interest and penalties, settlement	0	0	-12.7
Unrecognized tax benefits, interest and penalties, ending balance	4.1	10.2	7.4
Unrecognized tax benefits, income tax penalties and interest expense	-6.1	2.8	-1.3
Unrecognized tax benefits, reduction resulting from lapse of applicable statute of limitations	1.5	'	'
Expected cash payment related to settlement of IRS appeals	'	4.1	9.5
Unrecognized tax benefits, decrease resulting from cash and non-cash settlements with taxing authorities	$8.40	'	'

Income_Taxes_Refundable_Income

Income Taxes Refundable Income Taxes and Income Taxes Payable (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Refundable income taxes	$4.90	$4.70
Accrued income taxes, current	2.6	0.5
Sales and excise tax payable, current	$38.30	$27.10

Income_Taxes_Components_of_Def

Income Taxes Components of Deferred Tax Assets and Liabilities (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Valuation Allowance [Line Items]	'	'
Valuation allowance	$163.70	$166.10

Earnings_Per_Share_Earnings_Pe1

Earnings Per Share Earnings Per Share (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net income attributable to AAM	$29.80	$31.60	$25.80	$7.30	$319.90	($8.10)	$4.70	$51.20	$94.50	$367.70	$142.80
Basic shares outstanding - weighted average shares outstanding	'	'	'	'	'	'	'	'	76.7	75.3	74.9
Effect of dilutive securities - dilutive stock options	'	'	'	'	'	'	'	'	0.1	0.1	0.1
Effect of dilutive securities - dilutive warrants	'	'	'	'	'	'	'	'	0	0	0.4
Diluted shares outstanding - adjusted weighted-average shares after assumed conversions	'	'	'	'	'	'	'	'	76.8	75.4	75.4
Basic earnings per share	$0.39	$0.41	$0.34	$0.10	$4.21	($0.11)	$0.06	$0.68	$1.23	$4.88	$1.91
Diluted earnings per share	$0.39	$0.41	$0.34	$0.10	$4.21	($0.11)	$0.06	$0.68	$1.23	$4.87	$1.89
Retained Earnings [Member]	'	'	'	'	'	'	'	'	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net income attributable to AAM	'	'	'	'	'	'	'	'	$94.50	$367.70	$142.80

Earnings_Per_Share_Antidilutiv

Earnings Per Share Antidilutive Shares (Narrative) (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from computation of earnings per share, amount	2	3.3	4
Earnings per share, range of exercise prices of stock options excluded from the calculation of diluted EPS, lower end of range	$19.54	$15.58	$15.56
Earnings per share, range of exercise prices of stock options excluded from the calculation of diluted EPS, upper end of range	$40.83	$40.83	$40.83

Earnings_Per_Share_Warrants_Is

Earnings Per Share Warrants Issued to General Motors (Narrative) (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2009
2009 GM agreement, number of shares available for purchase through exercise of warrants	'	4.1
2009 GM agreement, exercise price of warrants issued to GM	'	$2.76
2008 GM agreement, shares issued to GM through exercise of warrants	3.3	'

Commitments_and_Contingencies_1

Commitments and Contingencies Purchase Obligations (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Long-term Purchase Commitment [Line Items]	'	'
Obligated purchase commitments	$161.40	$231.90

Commitments_and_Contingencies_2

Commitments and Contingencies Legal Proceedings (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2012
Defined benefit plan, cost of providing special or contractual termination benefits recognized during period	$28.70

Commitments_and_Contingencies_3

Commitments and Contingencies Product Liability (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Movement in Standard Product Warranty Accrual [Roll Forward]	'	'
Beginning balance	$29.10	$13.40
Accruals	12.8	23
Settlements	-12.3	-0.9
Adjustments to prior period accruals	-15	-6.4
Foreign currency translation and other	-0.3	0
Ending balance	14.3	29.1
Field Action [Member]	'	'
Movement in Standard Product Warranty Accrual [Roll Forward]	'	'
Accruals	2.3	9.9
Settlements	($11.30)	'

Reclassifications_out_of_Accum2

Reclassifications out of Accumulated Other Comprehensive Income Reclassifications out of Accumulated Other Comprehensive Income (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]	'	'	'
Defined benefit plans	($197.90)	($274.50)	'
Foreign currency translation adjustments	-18.6	7.6	'
Unrecognized gain on derivatives	0.3	2.3	'
Accumulated other comprehensive income (loss), net of tax	-216.2	-264.6	'
Total Other Comprehensive Income (Loss), Defined Benefit Plans, Net	-67.7	'	'
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax	-26.2	-9.4	-27.3
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax	0.8	'	'
Other Comprehensive Income (Loss) Arising During Period, Total, Net of Tax	42.3	'	'
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Net of Tax	8.9	'	'
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	0	'	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	-2.8	'	'
Other Comprehensive Income (Loss), Reclassification Adjustments, Total, Before Tax	6.1	'	'
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax	76.6	-58.9	-63.5
Foreign currency translation adjustments	-26.2	'	'
Change in derivatives	-2	7.8	-6.8
Other comprehensive income (loss)	48.4	-60.5	-97.6
Other comprehensive (income) loss, reclassification adjustment from AOCI, pension and other postretirement benefit plans, tax	-4.6	'	'
Other comprehensive (income) loss, pension and other postretirement benefit plans, before reclassification adjustments, tax	-36.7	'	'
Selling, General and Administrative Expenses [Member]	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]	'	'	'
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Net of Tax	4.2	'	'
Cost of Sales [Member]	'	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]	'	'	'
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net (Gain) Loss, Net of Tax	$4.70	'	'

Segment_and_Geographic_Informa2

Segment and Geographic Information Segment and Geographic Information (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	$831.30	$820.80	$799.60	$755.60	$736.70	$702.90	$739.80	$751.50	$3,207.30	$2,930.90	$2,585
Long-lived assets	1,689.40	'	'	'	1,627.80	'	'	'	1,689.40	1,627.80	1,545.50
United States [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	1,682	1,576.60	1,587.30
Long-lived assets	850	'	'	'	865.3	'	'	'	850	865.3	845.7
Segment, Geographical, Canada [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	74.4	75	60.8
Mexico [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	865.6	755.1	678.5
Long-lived assets	469.3	'	'	'	417.7	'	'	'	469.3	417.7	384.9
South America [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	201.1	216.4	134.8
Long-lived assets	100.2	'	'	'	113.3	'	'	'	100.2	113.3	131.9
Asia [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	255.2	214.5	33.2
Long-lived assets	176.7	'	'	'	159	'	'	'	176.7	159	131.7
Segment, Geographical, Other [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	129	93.3	90.4
Europe [Member]	'	'	'	'	'	'	'	'	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Long-lived assets	$93.20	'	'	'	$72.50	'	'	'	$93.20	$72.50	$51.30

Unaudited_Quarterly_Financial_2

Unaudited Quarterly Financial Data Unaudited Quarterly Financial Data (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net sales	$831.30	$820.80	$799.60	$755.60	$736.70	$702.90	$739.80	$751.50	$3,207.30	$2,930.90	$2,585
Gross profit	126.9	125.3	122.2	104.3	84	90.7	85.8	139.2	478.7	399.7	455.1
Net income (loss)	29.8	31.6	25.8	7.3	319.9	-8.2	4.7	50.3	94.5	366.7	137.1
Net income (loss) attributable to AAM	$29.80	$31.60	$25.80	$7.30	$319.90	($8.10)	$4.70	$51.20	$94.50	$367.70	$142.80
Basic earnings (loss) per share	$0.39	$0.41	$0.34	$0.10	$4.21	($0.11)	$0.06	$0.68	$1.23	$4.88	$1.91
Diluted earnings (loss) per share	$0.39	$0.41	$0.34	$0.10	$4.21	($0.11)	$0.06	$0.68	$1.23	$4.87	$1.89

Supplemental_Guarantor_Condens2

Supplemental Guarantor Condensed Consolidating Financial Statements 2013 Income Statement (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Ownership in subsidiary, percentage	100.00%	'	'	'	'	'	'	'	100.00%	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	$3,207.30	$2,930.90	$2,585
Intercompany	'	'	'	'	'	'	'	'	0	0	0
Total net sales	831.3	820.8	799.6	755.6	736.7	702.9	739.8	751.5	3,207.30	2,930.90	2,585
Cost of goods sold	'	'	'	'	'	'	'	'	2,728.60	2,531.20	2,129.90
Gross profit	126.9	125.3	122.2	104.3	84	90.7	85.8	139.2	478.7	399.7	455.1
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	238.4	243.3	231.7
Operating income	'	'	'	'	'	'	'	'	240.3	156.4	223.4
Non-operating income (expense), net	'	'	'	'	'	'	'	'	-154	-124.9	-85.3
Income (loss) before income taxes	'	'	'	'	'	'	'	'	86.3	31.5	138.1
Income tax expense (benefit)	'	'	'	'	'	'	'	'	-8.2	-335.2	1
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	94.5	366.7	137.1
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.5	366.7	137.1
Net loss attributable to the noncontrolling interests	'	'	'	'	'	'	'	'	0	1	5.7
Net income attributable to AAM	29.8	31.6	25.8	7.3	319.9	-8.1	4.7	51.2	94.5	367.7	142.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	48.4	-60.5	-97.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	142.9	306.9	45
Holdings [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	0	0	0
Intercompany	'	'	'	'	'	'	'	'	0	0	0
Total net sales	'	'	'	'	'	'	'	'	0	0	0
Cost of goods sold	'	'	'	'	'	'	'	'	0	0	0
Gross profit	'	'	'	'	'	'	'	'	0	0	0
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	0	0	0
Non-operating income (expense), net	'	'	'	'	'	'	'	'	0	0	0
Income (loss) before income taxes	'	'	'	'	'	'	'	'	0	0	0
Income tax expense (benefit)	'	'	'	'	'	'	'	'	0	0	0
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Net loss attributable to the noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	48.4	-60.5	-97.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	142.9	306.9	45
AAM Inc. [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	773.6	704.8	777.7
Intercompany	'	'	'	'	'	'	'	'	15.3	18.6	25.1
Total net sales	'	'	'	'	'	'	'	'	788.9	723.4	802.8
Cost of goods sold	'	'	'	'	'	'	'	'	769.4	709.8	727
Gross profit	'	'	'	'	'	'	'	'	19.5	13.6	75.8
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	182.4	186.5	192
Operating income	'	'	'	'	'	'	'	'	-162.9	-172.9	-116.2
Non-operating income (expense), net	'	'	'	'	'	'	'	'	-155.1	-135.2	-91.8
Income (loss) before income taxes	'	'	'	'	'	'	'	'	-318	-308.1	-208
Income tax expense (benefit)	'	'	'	'	'	'	'	'	-24.9	-343.9	-5.2
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	167	79	165.5
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	-126.1	114.8	-37.3
Royalties and dividends	'	'	'	'	'	'	'	'	220.6	252.9	180.1
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Net loss attributable to the noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	48.4	-60.5	-97.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	142.9	306.9	45
Guarantor Subsidiaries of Certain Notes [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	226	214.4	195.3
Intercompany	'	'	'	'	'	'	'	'	226.1	226.8	189.8
Total net sales	'	'	'	'	'	'	'	'	452.1	441.2	385.1
Cost of goods sold	'	'	'	'	'	'	'	'	389	389.8	334.2
Gross profit	'	'	'	'	'	'	'	'	63.1	51.4	50.9
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	0.1	0	0
Operating income	'	'	'	'	'	'	'	'	63	51.4	50.9
Non-operating income (expense), net	'	'	'	'	'	'	'	'	10.7	-2.2	1
Income (loss) before income taxes	'	'	'	'	'	'	'	'	73.7	49.2	51.9
Income tax expense (benefit)	'	'	'	'	'	'	'	'	0.9	-5.5	1.2
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	-21.7	-49.2	-37.7
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	51.1	5.5	13
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	51.1	5.5	13
Net loss attributable to the noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	51.1	5.5	13
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	-7.2	-10.1	-29
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0	0
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	43.9	-4.6	-16
Non-Guarantor Subsidiaries [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	2,207.70	2,011.70	1,612
Intercompany	'	'	'	'	'	'	'	'	14	25.2	12.7
Total net sales	'	'	'	'	'	'	'	'	2,221.70	2,036.90	1,624.70
Cost of goods sold	'	'	'	'	'	'	'	'	1,825.60	1,702.20	1,296.30
Gross profit	'	'	'	'	'	'	'	'	396.1	334.7	328.4
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	55.9	56.8	39.7
Operating income	'	'	'	'	'	'	'	'	340.2	277.9	288.7
Non-operating income (expense), net	'	'	'	'	'	'	'	'	-9.6	12.5	5.5
Income (loss) before income taxes	'	'	'	'	'	'	'	'	330.6	290.4	294.2
Income tax expense (benefit)	'	'	'	'	'	'	'	'	15.8	14.2	5
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	314.8	276.2	289.2
Royalties and dividends	'	'	'	'	'	'	'	'	-220.6	-252.9	-180.1
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.2	23.3	109.1
Net loss attributable to the noncontrolling interests	'	'	'	'	'	'	'	'	0	1	5.7
Net income attributable to AAM	'	'	'	'	'	'	'	'	94.2	24.3	114.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	-10.8	-3.6	-35.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	83.4	20.4	79
Consolidation, Eliminations [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	0	0	0
Intercompany	'	'	'	'	'	'	'	'	-255.4	-270.6	-227.6
Total net sales	'	'	'	'	'	'	'	'	-255.4	-270.6	-227.6
Cost of goods sold	'	'	'	'	'	'	'	'	-255.4	-270.6	-227.6
Gross profit	'	'	'	'	'	'	'	'	0	0	0
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	0	0	0
Non-operating income (expense), net	'	'	'	'	'	'	'	'	0	0	0
Income (loss) before income taxes	'	'	'	'	'	'	'	'	0	0	0
Income tax expense (benefit)	'	'	'	'	'	'	'	'	0	0	0
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Net loss attributable to the noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	-30.4	74.2	162.2
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	-0.6	-0.4
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	($270.20)	($322.70)	($108)

Supplemental_Guarantor_Condens3

Supplemental Guarantor Condensed Consolidating Financial Statements 2012 and 2011 Income Statements (Details) (USD $)	3 Months Ended								12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	$3,207.30	$2,930.90	$2,585
Intercompany	'	'	'	'	'	'	'	'	0	0	0
Total net sales	831.3	820.8	799.6	755.6	736.7	702.9	739.8	751.5	3,207.30	2,930.90	2,585
Cost of goods sold	'	'	'	'	'	'	'	'	2,728.60	2,531.20	2,129.90
Gross profit	126.9	125.3	122.2	104.3	84	90.7	85.8	139.2	478.7	399.7	455.1
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	238.4	243.3	231.7
Operating income	'	'	'	'	'	'	'	'	240.3	156.4	223.4
Non-operating income (expense), net	'	'	'	'	'	'	'	'	-154	-124.9	-85.3
Income (loss) before income taxes	'	'	'	'	'	'	'	'	86.3	31.5	138.1
Income tax expense (benefit)	'	'	'	'	'	'	'	'	-8.2	-335.2	1
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	94.5	366.7	137.1
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.5	366.7	137.1
Net loss attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	1	5.7
Net income attributable to AAM	29.8	31.6	25.8	7.3	319.9	-8.1	4.7	51.2	94.5	367.7	142.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	48.4	-60.5	-97.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	142.9	306.9	45
Holdings [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	0	0	0
Intercompany	'	'	'	'	'	'	'	'	0	0	0
Total net sales	'	'	'	'	'	'	'	'	0	0	0
Cost of goods sold	'	'	'	'	'	'	'	'	0	0	0
Gross profit	'	'	'	'	'	'	'	'	0	0	0
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	0	0	0
Non-operating income (expense), net	'	'	'	'	'	'	'	'	0	0	0
Income (loss) before income taxes	'	'	'	'	'	'	'	'	0	0	0
Income tax expense (benefit)	'	'	'	'	'	'	'	'	0	0	0
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Net loss attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	48.4	-60.5	-97.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	142.9	306.9	45
AAM Inc. [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	773.6	704.8	777.7
Intercompany	'	'	'	'	'	'	'	'	15.3	18.6	25.1
Total net sales	'	'	'	'	'	'	'	'	788.9	723.4	802.8
Cost of goods sold	'	'	'	'	'	'	'	'	769.4	709.8	727
Gross profit	'	'	'	'	'	'	'	'	19.5	13.6	75.8
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	182.4	186.5	192
Operating income	'	'	'	'	'	'	'	'	-162.9	-172.9	-116.2
Non-operating income (expense), net	'	'	'	'	'	'	'	'	-155.1	-135.2	-91.8
Income (loss) before income taxes	'	'	'	'	'	'	'	'	-318	-308.1	-208
Income tax expense (benefit)	'	'	'	'	'	'	'	'	-24.9	-343.9	-5.2
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	167	79	165.5
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	-126.1	114.8	-37.3
Royalties and dividends	'	'	'	'	'	'	'	'	220.6	252.9	180.1
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Net loss attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	94.5	367.7	142.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	48.4	-60.5	-97.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	142.9	306.9	45
Guarantor Subsidiaries of Certain Notes [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	226	214.4	195.3
Intercompany	'	'	'	'	'	'	'	'	226.1	226.8	189.8
Total net sales	'	'	'	'	'	'	'	'	452.1	441.2	385.1
Cost of goods sold	'	'	'	'	'	'	'	'	389	389.8	334.2
Gross profit	'	'	'	'	'	'	'	'	63.1	51.4	50.9
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	0.1	0	0
Operating income	'	'	'	'	'	'	'	'	63	51.4	50.9
Non-operating income (expense), net	'	'	'	'	'	'	'	'	10.7	-2.2	1
Income (loss) before income taxes	'	'	'	'	'	'	'	'	73.7	49.2	51.9
Income tax expense (benefit)	'	'	'	'	'	'	'	'	0.9	-5.5	1.2
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	-21.7	-49.2	-37.7
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	51.1	5.5	13
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	51.1	5.5	13
Net loss attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	51.1	5.5	13
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	-7.2	-10.1	-29
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0	0
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	43.9	-4.6	-16
Non-Guarantor Subsidiaries [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	2,207.70	2,011.70	1,612
Intercompany	'	'	'	'	'	'	'	'	14	25.2	12.7
Total net sales	'	'	'	'	'	'	'	'	2,221.70	2,036.90	1,624.70
Cost of goods sold	'	'	'	'	'	'	'	'	1,825.60	1,702.20	1,296.30
Gross profit	'	'	'	'	'	'	'	'	396.1	334.7	328.4
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	55.9	56.8	39.7
Operating income	'	'	'	'	'	'	'	'	340.2	277.9	288.7
Non-operating income (expense), net	'	'	'	'	'	'	'	'	-9.6	12.5	5.5
Income (loss) before income taxes	'	'	'	'	'	'	'	'	330.6	290.4	294.2
Income tax expense (benefit)	'	'	'	'	'	'	'	'	15.8	14.2	5
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	314.8	276.2	289.2
Royalties and dividends	'	'	'	'	'	'	'	'	-220.6	-252.9	-180.1
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	94.2	23.3	109.1
Net loss attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	1	5.7
Net income attributable to AAM	'	'	'	'	'	'	'	'	94.2	24.3	114.8
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	-10.8	-3.6	-35.6
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	0.3	0.2
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	83.4	20.4	79
Consolidation, Eliminations [Member]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	'	'	'
External	'	'	'	'	'	'	'	'	0	0	0
Intercompany	'	'	'	'	'	'	'	'	-255.4	-270.6	-227.6
Total net sales	'	'	'	'	'	'	'	'	-255.4	-270.6	-227.6
Cost of goods sold	'	'	'	'	'	'	'	'	-255.4	-270.6	-227.6
Gross profit	'	'	'	'	'	'	'	'	0	0	0
Selling, general and administrative expenses	'	'	'	'	'	'	'	'	0	0	0
Operating income	'	'	'	'	'	'	'	'	0	0	0
Non-operating income (expense), net	'	'	'	'	'	'	'	'	0	0	0
Income (loss) before income taxes	'	'	'	'	'	'	'	'	0	0	0
Income tax expense (benefit)	'	'	'	'	'	'	'	'	0	0	0
Earnings (loss) from equity in subsidiaries	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Net income (loss) before royalties and dividends	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Royalties and dividends	'	'	'	'	'	'	'	'	0	0	0
Net income (loss) after royalties and dividends	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Net loss attributable to noncontrolling interests	'	'	'	'	'	'	'	'	0	0	0
Net income attributable to AAM	'	'	'	'	'	'	'	'	-239.8	-397.5	-270.6
Other comprehensive income (loss), net of tax	'	'	'	'	'	'	'	'	-30.4	74.2	162.2
Foreign currency translation adjustments attributable to noncontrolling interests	'	'	'	'	'	'	'	'	'	-0.6	-0.4
Comprehensive income attributable to AAM	'	'	'	'	'	'	'	'	($270.20)	($322.70)	($108)

Supplemental_Guarantor_Condens4

Supplemental Guarantor Condensed Consolidating Financial Statements 2013 and 2012 Balance Sheets (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Millions, unless otherwise specified
Current Assets	'	'	'	'
Cash and cash equivalents	$154	$62.40	$169.20	$244.60
Accounts receivable, net	458.5	463.4	'	'
Inventories, net	261.8	224.3	'	'
Other current assets	123.5	122	'	'
Total current assets	997.8	872.1	'	'
Property, plant and equipment, net	1,058.50	1,009.70	'	'
Goodwill	156.4	156.4	155.9	'
Other assets and deferred charges	816.3	827.8	'	'
Investment in subsidiaries	0	0	'	'
Total assets	3,029	2,866	'	'
Current Liabilities	'	'	'	'
Accounts Payable	445.8	396.1	'	'
Other current liabilities	221.3	204.7	'	'
Total current liabilities	667.1	600.8	'	'
Intercompany payable (receivable)	0	0	'	'
Long-term debt	1,559.10	1,454.10	'	'
Investment in subsidiaries obligation	0	0	'	'
Other liabilities, noncurrent	769.2	931.9	'	'
Total liabilities	2,995.40	2,986.80	'	'
Total AAM stockholders' equity (deficit)	33.6	-120.8	'	'
Noncontrolling interest in subsidiaries	0	0	5.9	11.4
Total stockholders’ equity (deficit)	33.6	-120.8	'	'
Total liabilities and stockholders' equity (deficit)	3,029	2,866	'	'
Holdings [Member]	'	'	'	'
Current Assets	'	'	'	'
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0	'	'
Inventories, net	0	0	'	'
Other current assets	0	0	'	'
Total current assets	0	0	'	'
Property, plant and equipment, net	0	0	'	'
Goodwill	0	0	'	'
Other assets and deferred charges	0	0	'	'
Investment in subsidiaries	360.5	202.9	'	'
Total assets	360.5	202.9	'	'
Current Liabilities	'	'	'	'
Accounts Payable	0	0	'	'
Other current liabilities	0	0	'	'
Total current liabilities	0	0	'	'
Intercompany payable (receivable)	326.9	323.7	'	'
Long-term debt	0	0	'	'
Investment in subsidiaries obligation	0	0	'	'
Other liabilities, noncurrent	0	0	'	'
Total liabilities	326.9	323.7	'	'
Total AAM stockholders' equity (deficit)	33.6	-120.8	'	'
Noncontrolling interest in subsidiaries	0	0	'	'
Total stockholders’ equity (deficit)	33.6	-120.8	'	'
Total liabilities and stockholders' equity (deficit)	360.5	202.9	'	'
AAM Inc. [Member]	'	'	'	'
Current Assets	'	'	'	'
Cash and cash equivalents	36.9	10.6	83.7	67.6
Accounts receivable, net	102.7	94.4	'	'
Inventories, net	62.4	48.7	'	'
Other current assets	43.8	48.8	'	'
Total current assets	245.8	202.5	'	'
Property, plant and equipment, net	239.8	250.4	'	'
Goodwill	0	0	'	'
Other assets and deferred charges	671.7	706.1	'	'
Investment in subsidiaries	1,233.20	1,094.60	'	'
Total assets	2,390.50	2,253.60	'	'
Current Liabilities	'	'	'	'
Accounts Payable	106.2	91.4	'	'
Other current liabilities	120.4	124.5	'	'
Total current liabilities	226.6	215.9	'	'
Intercompany payable (receivable)	-390.1	-420.6	'	'
Long-term debt	1,500	1,387.50	'	'
Investment in subsidiaries obligation	0	0	'	'
Other liabilities, noncurrent	693.5	867.9	'	'
Total liabilities	2,030	2,050.70	'	'
Total AAM stockholders' equity (deficit)	360.5	202.9	'	'
Noncontrolling interest in subsidiaries	0	0	'	'
Total stockholders’ equity (deficit)	360.5	202.9	'	'
Total liabilities and stockholders' equity (deficit)	2,390.50	2,253.60	'	'
Guarantor Subsidiaries of Certain Notes [Member]	'	'	'	'
Current Assets	'	'	'	'
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	25.6	25.3	'	'
Inventories, net	34.2	31.6	'	'
Other current assets	3.2	3.5	'	'
Total current assets	63	60.4	'	'
Property, plant and equipment, net	83	84.2	'	'
Goodwill	147.8	147.8	'	'
Other assets and deferred charges	44.8	40	'	'
Investment in subsidiaries	0	0	'	'
Total assets	338.6	332.4	'	'
Current Liabilities	'	'	'	'
Accounts Payable	44.5	37.3	'	'
Other current liabilities	4.1	3.8	'	'
Total current liabilities	48.6	41.1	'	'
Intercompany payable (receivable)	-219.5	-188.7	'	'
Long-term debt	5.3	5.6	'	'
Investment in subsidiaries obligation	15.2	7.6	'	'
Other liabilities, noncurrent	0.5	1.2	'	'
Total liabilities	-149.9	-133.2	'	'
Total AAM stockholders' equity (deficit)	488.5	465.6	'	'
Noncontrolling interest in subsidiaries	0	0	'	'
Total stockholders’ equity (deficit)	488.5	465.6	'	'
Total liabilities and stockholders' equity (deficit)	338.6	332.4	'	'
Non-Guarantor Subsidiaries [Member]	'	'	'	'
Current Assets	'	'	'	'
Cash and cash equivalents	117.1	51.8	85.5	177
Accounts receivable, net	330.2	343.7	'	'
Inventories, net	165.2	144	'	'
Other current assets	76.5	69.7	'	'
Total current assets	689	609.2	'	'
Property, plant and equipment, net	735.7	675.1	'	'
Goodwill	8.6	8.6	'	'
Other assets and deferred charges	99.8	81.7	'	'
Investment in subsidiaries	0	0	'	'
Total assets	1,533.10	1,374.60	'	'
Current Liabilities	'	'	'	'
Accounts Payable	295.1	267.4	'	'
Other current liabilities	96.8	76.4	'	'
Total current liabilities	391.9	343.8	'	'
Intercompany payable (receivable)	282.7	285.6	'	'
Long-term debt	53.8	61	'	'
Investment in subsidiaries obligation	0	0	'	'
Other liabilities, noncurrent	75.2	62.8	'	'
Total liabilities	803.6	753.2	'	'
Total AAM stockholders' equity (deficit)	729.5	621.4	'	'
Noncontrolling interest in subsidiaries	0	0	'	'
Total stockholders’ equity (deficit)	729.5	621.4	'	'
Total liabilities and stockholders' equity (deficit)	1,533.10	1,374.60	'	'
Consolidation, Eliminations [Member]	'	'	'	'
Current Assets	'	'	'	'
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0	'	'
Inventories, net	0	0	'	'
Other current assets	0	0	'	'
Total current assets	0	0	'	'
Property, plant and equipment, net	0	0	'	'
Goodwill	0	0	'	'
Other assets and deferred charges	0	0	'	'
Investment in subsidiaries	-1,593.70	-1,297.50	'	'
Total assets	-1,593.70	-1,297.50	'	'
Current Liabilities	'	'	'	'
Accounts Payable	0	0	'	'
Other current liabilities	0	0	'	'
Total current liabilities	0	0	'	'
Intercompany payable (receivable)	0	0	'	'
Long-term debt	0	0	'	'
Investment in subsidiaries obligation	-15.2	-7.6	'	'
Other liabilities, noncurrent	0	0	'	'
Total liabilities	-15.2	-7.6	'	'
Total AAM stockholders' equity (deficit)	-1,578.50	-1,289.90	'	'
Noncontrolling interest in subsidiaries	0	0	'	'
Total stockholders’ equity (deficit)	-1,578.50	-1,289.90	'	'
Total liabilities and stockholders' equity (deficit)	($1,593.70)	($1,297.50)	'	'

Supplemental_Guarantor_Condens5

Supplemental Guarantor Condensed Consolidating Financial Statements 2013 and 2012 Cash Flow Statements (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net cash provided by (used in) operating activities	$223	($175.50)	($56.30)
Investing activities	'	'	'
Purchases of property, plant and equipment	-251.9	-207.6	-163.1
Proceeds from sale of property, plant and equipment	9.1	10.1	8.9
Proceeds from sale-leaseback of equipment	24.1	12.1	0
Purchase buyouts of leased equipment	0	0	-13.4
Acquisition, net	'	'	-16.5
Net cash used in investing activities	-218.7	-185.4	-184.1
Financing activities	'	'	'
Net debt activity	104.8	273.9	173.6
Intercompany activity	0	0	0
Debt issuance costs	-16.7	-10.6	-10.9
Employee stock option exercises, including tax benefit	1.1	0.1	4.6
Purchase of treasury stock	-0.4	-5.9	-0.1
Purchase of noncontrolling interest	0	-4	0
Net cash provided by financing activities	88.8	253.5	167.2
Effect of exchange rate changes on cash	-1.5	0.6	-2.2
Net increase (decrease) in cash and cash equivalents	91.6	-106.8	-75.4
Cash and cash equivalents at beginning of year	62.4	169.2	244.6
Cash and cash equivalents at end of year	154	62.4	169.2
Holdings [Member]	'	'	'
Net cash provided by (used in) operating activities	0	0	0
Investing activities	'	'	'
Purchases of property, plant and equipment	0	0	0
Proceeds from sale of property, plant and equipment	0	0	0
Proceeds from sale-leaseback of equipment	0	0	'
Purchase buyouts of leased equipment	'	'	0
Acquisition, net	'	'	0
Net cash used in investing activities	0	0	0
Financing activities	'	'	'
Net debt activity	0	0	0
Intercompany activity	0.4	5.9	0.1
Debt issuance costs	0	0	0
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	-0.4	-5.9	-0.1
Purchase of noncontrolling interest	'	0	'
Net cash provided by financing activities	0	0	0
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
AAM Inc. [Member]	'	'	'
Net cash provided by (used in) operating activities	-70.4	-228.2	-119.3
Investing activities	'	'	'
Purchases of property, plant and equipment	-61.2	-59.4	-43.9
Proceeds from sale of property, plant and equipment	5.1	7	1.5
Proceeds from sale-leaseback of equipment	24.1	12.1	'
Purchase buyouts of leased equipment	'	'	-13.4
Acquisition, net	'	'	0
Net cash used in investing activities	-32	-40.3	-55.8
Financing activities	'	'	'
Net debt activity	110.1	257.9	159.6
Intercompany activity	34.1	-52	37.9
Debt issuance costs	-16.6	-10.6	-10.9
Employee stock option exercises, including tax benefit	1.1	0.1	4.6
Purchase of treasury stock	0	0	0
Purchase of noncontrolling interest	'	0	'
Net cash provided by financing activities	128.7	195.4	191.2
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	26.3	-73.1	16.1
Cash and cash equivalents at beginning of year	10.6	83.7	67.6
Cash and cash equivalents at end of year	36.9	10.6	83.7
Guarantor Subsidiaries of Certain Notes [Member]	'	'	'
Net cash provided by (used in) operating activities	84.9	56.8	40.1
Investing activities	'	'	'
Purchases of property, plant and equipment	-12.5	-9	-4.9
Proceeds from sale of property, plant and equipment	0.5	0	0
Proceeds from sale-leaseback of equipment	0	0	'
Purchase buyouts of leased equipment	'	'	0
Acquisition, net	'	'	-16.5
Net cash used in investing activities	-12	-9	-21.4
Financing activities	'	'	'
Net debt activity	-0.3	-0.2	-0.2
Intercompany activity	-72.6	-47.6	-18.5
Debt issuance costs	0	0	0
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	0	0	0
Purchase of noncontrolling interest	'	0	'
Net cash provided by financing activities	-72.9	-47.8	-18.7
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
Non-Guarantor Subsidiaries [Member]	'	'	'
Net cash provided by (used in) operating activities	208.5	-4.1	22.9
Investing activities	'	'	'
Purchases of property, plant and equipment	-178.2	-139.2	-114.3
Proceeds from sale of property, plant and equipment	3.5	3.1	7.4
Proceeds from sale-leaseback of equipment	0	0	'
Purchase buyouts of leased equipment	'	'	0
Acquisition, net	'	'	0
Net cash used in investing activities	-174.7	-136.1	-106.9
Financing activities	'	'	'
Net debt activity	-5	16.2	14.2
Intercompany activity	38.1	93.7	-19.5
Debt issuance costs	-0.1	0	0
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	0	0	0
Purchase of noncontrolling interest	'	-4	'
Net cash provided by financing activities	33	105.9	-5.3
Effect of exchange rate changes on cash	-1.5	0.6	-2.2
Net increase (decrease) in cash and cash equivalents	65.3	-33.7	-91.5
Cash and cash equivalents at beginning of year	51.8	85.5	177
Cash and cash equivalents at end of year	117.1	51.8	85.5
Consolidation, Eliminations [Member]	'	'	'
Net cash provided by (used in) operating activities	0	0	0
Investing activities	'	'	'
Purchases of property, plant and equipment	0	0	0
Proceeds from sale of property, plant and equipment	0	0	0
Proceeds from sale-leaseback of equipment	0	0	'
Purchase buyouts of leased equipment	'	'	0
Acquisition, net	'	'	0
Net cash used in investing activities	0	0	0
Financing activities	'	'	'
Net debt activity	0	0	0
Intercompany activity	0	0	0
Debt issuance costs	0	0	0
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	0	0	0
Purchase of noncontrolling interest	'	0	'
Net cash provided by financing activities	0	0	0
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	$0	$0	$0

Supplemental_Guarantor_Condens6

Supplemental Guarantor Condensed Consolidating Financial Statements 2011 Cash Flow Statement (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net cash provided by (used in) operating activities	$223	($175.50)	($56.30)
Investing activities	'	'	'
Purchases of property, plant and equipment	-251.9	-207.6	-163.1
Proceeds from sale of property, plant and equipment	9.1	10.1	8.9
Acquisition, net	'	'	-16.5
Purchase buyouts of leased equipment	0	0	-13.4
Net cash used in investing activities	-218.7	-185.4	-184.1
Financing activities	'	'	'
Net debt activity	104.8	273.9	173.6
Intercompany activity	0	0	0
Debt issuance costs	-16.7	-10.6	-10.9
Purchase of noncontrolling interest	0	-4	0
Employee stock option exercises, including tax benefit	1.1	0.1	4.6
Purchase of treasury stock	-0.4	-5.9	-0.1
Net cash provided by financing activities	88.8	253.5	167.2
Effect of exchange rate changes on cash	-1.5	0.6	-2.2
Net increase (decrease) in cash and cash equivalents	91.6	-106.8	-75.4
Cash and cash equivalents at beginning of year	62.4	169.2	244.6
Cash and cash equivalents at end of year	154	62.4	169.2
Holdings [Member]	'	'	'
Net cash provided by (used in) operating activities	0	0	0
Investing activities	'	'	'
Purchases of property, plant and equipment	0	0	0
Proceeds from sale of property, plant and equipment	0	0	0
Acquisition, net	'	'	0
Purchase buyouts of leased equipment	'	'	0
Net cash used in investing activities	0	0	0
Financing activities	'	'	'
Net debt activity	0	0	0
Intercompany activity	0.4	5.9	0.1
Debt issuance costs	0	0	0
Purchase of noncontrolling interest	'	0	'
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	-0.4	-5.9	-0.1
Net cash provided by financing activities	0	0	0
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
AAM Inc. [Member]	'	'	'
Net cash provided by (used in) operating activities	-70.4	-228.2	-119.3
Investing activities	'	'	'
Purchases of property, plant and equipment	-61.2	-59.4	-43.9
Proceeds from sale of property, plant and equipment	5.1	7	1.5
Acquisition, net	'	'	0
Purchase buyouts of leased equipment	'	'	-13.4
Net cash used in investing activities	-32	-40.3	-55.8
Financing activities	'	'	'
Net debt activity	110.1	257.9	159.6
Intercompany activity	34.1	-52	37.9
Debt issuance costs	-16.6	-10.6	-10.9
Purchase of noncontrolling interest	'	0	'
Employee stock option exercises, including tax benefit	1.1	0.1	4.6
Purchase of treasury stock	0	0	0
Net cash provided by financing activities	128.7	195.4	191.2
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	26.3	-73.1	16.1
Cash and cash equivalents at beginning of year	10.6	83.7	67.6
Cash and cash equivalents at end of year	36.9	10.6	83.7
Guarantor Subsidiaries of Certain Notes [Member]	'	'	'
Net cash provided by (used in) operating activities	84.9	56.8	40.1
Investing activities	'	'	'
Purchases of property, plant and equipment	-12.5	-9	-4.9
Proceeds from sale of property, plant and equipment	0.5	0	0
Acquisition, net	'	'	-16.5
Purchase buyouts of leased equipment	'	'	0
Net cash used in investing activities	-12	-9	-21.4
Financing activities	'	'	'
Net debt activity	-0.3	-0.2	-0.2
Intercompany activity	-72.6	-47.6	-18.5
Debt issuance costs	0	0	0
Purchase of noncontrolling interest	'	0	'
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	0	0	0
Net cash provided by financing activities	-72.9	-47.8	-18.7
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
Non-Guarantor Subsidiaries [Member]	'	'	'
Net cash provided by (used in) operating activities	208.5	-4.1	22.9
Investing activities	'	'	'
Purchases of property, plant and equipment	-178.2	-139.2	-114.3
Proceeds from sale of property, plant and equipment	3.5	3.1	7.4
Acquisition, net	'	'	0
Purchase buyouts of leased equipment	'	'	0
Net cash used in investing activities	-174.7	-136.1	-106.9
Financing activities	'	'	'
Net debt activity	-5	16.2	14.2
Intercompany activity	38.1	93.7	-19.5
Debt issuance costs	-0.1	0	0
Purchase of noncontrolling interest	'	-4	'
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	0	0	0
Net cash provided by financing activities	33	105.9	-5.3
Effect of exchange rate changes on cash	-1.5	0.6	-2.2
Net increase (decrease) in cash and cash equivalents	65.3	-33.7	-91.5
Cash and cash equivalents at beginning of year	51.8	85.5	177
Cash and cash equivalents at end of year	117.1	51.8	85.5
Consolidation, Eliminations [Member]	'	'	'
Net cash provided by (used in) operating activities	0	0	0
Investing activities	'	'	'
Purchases of property, plant and equipment	0	0	0
Proceeds from sale of property, plant and equipment	0	0	0
Acquisition, net	'	'	0
Purchase buyouts of leased equipment	'	'	0
Net cash used in investing activities	0	0	0
Financing activities	'	'	'
Net debt activity	0	0	0
Intercompany activity	0	0	0
Debt issuance costs	0	0	0
Purchase of noncontrolling interest	'	0	'
Employee stock option exercises, including tax benefit	0	0	0
Purchase of treasury stock	0	0	0
Net cash provided by financing activities	0	0	0
Effect of exchange rate changes on cash	0	0	0
Net increase (decrease) in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	$0	$0	$0

Schedule_II_Valuation_and_Qual1

Schedule II - Valuation and Qualifying Accounts Schedule II - Valuation and Qualifying Accounts (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Valuation and Qualifying Accounts Disclosure [Line Items]	'	'	'	'
Allowance for doubtful accounts	$4.90	$6.50	'	'
Allowance for deferred taxes	163.7	166.1	'	'
Inventory valuation allowance	27.3	21	'	'
Allowance for Doubtful Accounts [Member]	'	'	'	'
Valuation and Qualifying Accounts Disclosure [Line Items]	'	'	'	'
Allowance for doubtful accounts	4.9	6.5	5.5	6.2
Additions, charged to costs and expenses	2.3	2	3.3	'
Deductions	3.9	1	4	'
Valuation Allowance of Deferred Tax Assets [Member]	'	'	'	'
Valuation and Qualifying Accounts Disclosure [Line Items]	'	'	'	'
Allowance for deferred taxes	163.7	166.1	426.9	560.9
Additions, charged to costs and expenses	14	80.9	14.6	'
Deductions	16.4	341.7	148.6	'
Inventory Valuation Reserve [Member]	'	'	'	'
Valuation and Qualifying Accounts Disclosure [Line Items]	'	'	'	'
Inventory valuation allowance	27.3	21	26.7	27.7
Additions, charged to costs and expenses	19.4	7.9	6.3	'
Deductions	$13.10	$13.60	$7.30	'