Altra Industrial Motion (AIMC) 10-K26 Feb 142013 FY Annual reportFinancial data

Company Profile

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Feb. 19, 2014	Jun. 29, 2013
Document And Entity Information [Abstract]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Entity Registrant Name	'ALTRA INDUSTRIAL MOTION CORP.	'	'
Entity Central Index Key	'0001374535	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	27,053,037	'
Entity Public Float	'	'	$712.20

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Current assets:	'	'
Cash and cash equivalents	$63,604	$85,154
Trade receivables, less allowance for doubtful accounts of $2,245 and $2,560 at December 31, 2013 and 2012, respectively	109,084	92,933
Inventories	143,665	123,776
Deferred income taxes	9,754	8,918
Income tax receivable	5,032	6,397
Prepaid expenses and other current assets	18,066	6,578
Total current assets	349,205	323,756
Property, plant and equipment, net	157,535	138,094
Intangible assets, net	118,768	76,098
Goodwill	104,339	88,225
Deferred income taxes	934	1,150
Other non-current assets, net	4,895	5,716
Total assets	735,676	633,039
Current liabilities:	'	'
Accounts payable	51,180	43,042
Accrued payroll	23,983	19,893
Accruals and other current liabilities	34,979	31,084
Income tax payable	12,963	2,712
Deferred income taxes	44	34
Current portion of long-term debt	16,924	9,135
Total current liabilities	140,073	105,900
Long-term debt - less current portion and net of unaccreted discount	261,348	238,460
Deferred income taxes	53,813	38,821
Pension liabilities	8,025	14,529
Long-term taxes payable	1,038	1,118
Other long-term liabilities	1,055	960
Redeemable non-controlling interest	991	1,239
Stockholders' equity:	'	'
Commitments and Contingencies (Note 14)	'	'
Preferred stock ($0.0001 par value, 10,000,000 shares authorized, none issued and outstanding at December 31, 2013 and 2012, respectively)	'	'
Common stock ($0.001 par value, 90,000,000 shares authorized, 26,819,795 and 26,724,349 issued and outstanding at December 31, 2013 and 2012, respectively)	27	27
Additional paid-in capital	154,471	152,188
Retained earnings	133,231	103,200
Accumulated other comprehensive loss	-18,396	-23,403
Total stockholders' equity	269,333	232,012
Total liabilities, non-controlling interest and stockholders' equity	$735,676	$633,039

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]	'	'
Allowance for doubtful accounts	$2,245	$2,560
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	90,000,000	90,000,000
Common stock, shares issued	26,819,795	26,724,349
Common stock, shares outstanding	26,819,795	26,724,349

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]	'	'	'
Net sales	$722,218	$731,990	$674,812
Cost of sales	506,837	513,442	478,394
Gross profit	215,381	218,548	196,418
Operating expenses:	'	'	'
Selling, general and administrative expenses	130,155	127,044	113,375
Research and development expenses	12,536	11,457	10,609
Restructuring costs	1,111	3,196	0
Total operating expenses	143,802	141,697	123,984
Income from operations	71,579	76,851	72,434
Other non-operating income and expense:	'	'	'
Interest expense, net	10,586	40,790	24,035
Other non-operating expense (income), net	1,657	1,702	-32
Total other non-operating income expense, net	12,243	42,492	24,003
Income before income taxes	59,336	34,359	48,431
Provision for income taxes	19,151	10,154	10,756
Net income	40,185	24,205	37,675
Net loss attributable to non-controlling interest	90	88	'
Net income attributable to Altra Industrial Motion Corp.	40,275	24,293	37,675
Consolidated Statement of Comprehensive Income	'	'	'
Pension liability adjustment, net of tax	1,474	-2,122	-1,603
Change in fair value of interest rate swap, net of tax	135	'	'
Foreign currency translation adjustment, net of tax	3,398	3,795	-8,802
Total comprehensive income	45,192	25,966	27,270
Comprehensive loss attributable to non-controlling interest	248	'	'
Comprehensive income attributable to Altra Industrial Motion Corp.	$45,440	$25,966	$27,270
Weighted average shares, basic	26,766	26,656	26,526
Weighted average shares, diluted	26,841	26,756	26,689
Earnings per share:	'	'	'
Basic net income attributable to Altra Industrial Motion Corp.	$1.50	$0.91	$1.42
Diluted net income attributable to Altra Industrial Motion Corp.	$1.50	$0.91	$1.41
Cash dividend declared	$0.38	$0.16	'

Consolidated_Statement_of_Stoc

Consolidated Statement of Stockholders' Equity (USD $)	Total	Common Stock [Member]	Additional Paid in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Redeemable Non-Controlling Interest [Member]
In Thousands, except Share data	Total	Common Stock [Member]	Additional Paid in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Redeemable Non-Controlling Interest [Member]
Beginning Balance at Dec. 31, 2010	$164,752	$26	$133,861	$45,536	($14,671)	'
Beginning Balance, Shares at Dec. 31, 2010	'	26,466	'	'	'	'
Stock based compensation and vesting of restricted stock	1,820	1	1,819	'	'	'
Stock based compensation and vesting of restricted stock, Shares	'	134	'	'	'	'
Net income attributable to Altra Industrial Motion Corp.	37,675	'	'	37,675	'	'
Convertible Notes	24,510	'	24,510	'	'	'
Deferred taxes on Convertible Notes	-8,966	'	-8,966	'	'	'
Deferred financing costs on Convertible Notes	-990	'	-990	'	'	'
Cumulative foreign currency translation adjustment, net of $731, $994 and $50 of tax expense for 2011, 2012 and 2013 respectively	-8,802	'	'	'	-8,802	'
Minimum Pension adjustment, net of $868, $1,388 and $800 tax expense for 2011, 2012 and 2013 respectively	-1,603	'	'	'	-1,603	'
Ending Balance at Dec. 31, 2011	208,396	27	150,234	83,211	-25,076	'
Ending Balance, Shares at Dec. 31, 2011	'	26,600	'	'	'	'
Stock based compensation and vesting of restricted stock	1,954	'	1,954	'	'	'
Stock based compensation and vesting of restricted stock, Shares	'	124	'	'	'	'
Net income attributable to Altra Industrial Motion Corp.	24,293	'	'	24,293	'	'
Net loss attributable to non-controlling interest	-88	'	'	'	'	-88
Fair value of non-controlling interest at acquisition	'	'	'	'	'	1,327
Dividends declared	-4,304	'	'	-4,304	'	'
Cumulative foreign currency translation adjustment, net of $731, $994 and $50 of tax expense for 2011, 2012 and 2013 respectively	3,795	'	'	'	3,795	'
Minimum Pension adjustment, net of $868, $1,388 and $800 tax expense for 2011, 2012 and 2013 respectively	-2,122	'	'	'	-2,122	'
Ending Balance at Dec. 31, 2012	232,012	27	152,188	103,200	-23,403	1,239
Ending Balance, Shares at Dec. 31, 2012	'	26,724	'	'	'	'
Stock based compensation and vesting of restricted stock	2,283	'	2,283	'	'	'
Stock based compensation and vesting of restricted stock, Shares	'	96	'	'	'	'
Net income attributable to Altra Industrial Motion Corp.	40,275	'	'	40,275	'	'
Net loss attributable to non-controlling interest	-90	'	'	'	'	-90
Dividends declared	-10,244	'	'	-10,244	'	'
Cumulative foreign currency translation adjustment, net of $731, $994 and $50 of tax expense for 2011, 2012 and 2013 respectively	3,398	'	'	'	3,398	-158
Change in fair value of interest rate swap, net of $78 tax expense	135	'	'	'	135	'
Minimum Pension adjustment, net of $868, $1,388 and $800 tax expense for 2011, 2012 and 2013 respectively	1,474	'	'	'	1,474	'
Ending Balance at Dec. 31, 2013	$269,333	$27	$154,471	$133,231	($18,396)	$991
Ending Balance, Shares at Dec. 31, 2013	'	26,820	'	'	'	'

Consolidated_Statement_of_Stoc1

Consolidated Statement of Stockholders' Equity (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Change in fair value of interest rate swap, tax expense	$78	'	'
Minimum Pension adjustment, tax expense	800	1,388	868
Tax expense for foreign currency	50	994	731
Accumulated Other Comprehensive Loss [Member]	'	'	'
Change in fair value of interest rate swap, tax expense	78	'	'
Minimum Pension adjustment, tax expense	800	1,388	868
Tax expense for foreign currency	$50	$994	$731

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities	'	'	'
Net income	$40,185	$24,205	$37,675
Adjustments to reconcile net income to net cash flows provided by operating activities:	'	'	'
Depreciation	21,419	20,537	18,403
Amortization of intangible assets	6,505	6,839	6,280
Amortization and write-offs of deferred loan costs	873	6,006	1,833
(Gain) loss on foreign currency, net	742	-125	843
Accretion and write-off of debt discount and premium	3,143	4,869	2,696
Loss on disposal/impairment of fixed assets	147	251	287
Amortization of inventory fair value adjustment	'	122	581
Stock based compensation	3,173	2,696	2,471
Provision (benefit) for deferred taxes	3,464	-625	4,879
Changes in assets and liabilities:	'	'	'
Trade receivables	5,791	836	-9,379
Inventories	6,412	4,084	-19,948
Accounts payable and accrued liabilities	-708	-6,640	8,839
Other current assets and liabilities	2,156	726	-1,344
Other operating assets and liabilities	-3,677	-3,863	-7,215
Net cash provided by operating activities	89,625	59,918	46,901
Cash flows from investing activities	'	'	'
Purchase of property, plant and equipment	-27,823	-31,346	-22,242
Proceeds from sale of Facility	'	'	1,484
Net cash used in investing activities	-130,005	-38,770	-89,887
Cash flows from financing activities	'	'	'
Payment of debt issuance costs	-670	-2,454	-3,674
Payment on mortgages and other debt	-756	-1,199	-547
Borrowing under Revolving Credit Facility	21,198	'	'
Borrowing under Additional Term Loan	68,871	'	'
Proceeds from issuance of Convertible Notes	'	'	85,000
Payments on Former Term Loan Facility	-5,625	'	'
Payments on Former Revolving Credit Facility	-59,304	'	'
Proceeds from Former Term Loan Facility and Revolving Credit Facility	'	179,304	'
Proceeds from Equipment Loan	2,999	1,100	'
Shares surrendered for tax withholding	-1,174	-949	-944
Dividend payments	-7,548	-4,304	'
Net payments on capital leases	'	-333	-825
Net cash provided by financing activities	17,991	-29,880	64,765
Effect of exchange rate changes on cash and cash equivalents	839	1,371	-1,987
Net change in cash and cash equivalents	-21,550	-7,361	19,792
Cash and cash equivalents at beginning of year	85,154	92,515	72,723
Cash and cash equivalents at end of period	63,604	85,154	92,515
Cash paid during the period for:	'	'	'
Interest	6,704	30,891	18,724
Income taxes	13,398	12,397	11,860
Non-cash Financing and Investing:	'	'	'
Acquisition of property, plant and equipment included in accounts payable	1,179	574	577
Dividend accrued	2,696	'	'
Mortgage receivable on sale of Stratford facility	'	'	623
Stratford Facility [Member]	'	'	'
Cash flows from investing activities	'	'	'
Proceeds from sale of Facility	'	'	331
Mt Pleasant Facility (Member)	'	'	'
Cash flows from investing activities	'	'	'
Proceeds from sale of Facility	578	'	'
Svendborg [Member]	'	'	'
Cash flows from investing activities	'	'	'
Acquisition, net of cash received	-94,613	'	'
Cash paid to escrow agent for Svendborg Transfer Pricing Claim liability	-8,147	'	'
Lamiflex [Member]	'	'	'
Cash flows from investing activities	'	'	'
Acquisition, net of cash received	'	-7,424	'
Bauer [Member]	'	'	'
Cash flows from investing activities	'	'	'
Acquisition, net of cash received	'	'	-69,460
Senior Secured Notes [Member]	'	'	'
Cash flows from financing activities	'	'	'
Purchase of 8 1 /8 % Senior Secured Notes	'	-198,045	-11,955
Chattanooga Facility [Member]	'	'	'
Cash flows from financing activities	'	'	'
Redemption of variable rate demand revenue bonds	'	'	-2,290
San Marcos [Member]	'	'	'
Cash flows from financing activities	'	'	'
Redemption of variable rate demand revenue bonds	'	($3,000)	'

Consolidated_Statements_of_Cas1

Consolidated Statements of Cash Flows (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Svendborg [Member]	Lamiflex [Member]	Bauer [Member]	Senior Secured Notes [Member]	Senior Secured Notes [Member]	Senior Secured Notes [Member]
Cash acquired from acquisition	$7,500	$68	$41	'	'	'
Interest rate on Senior Secured Notes	'	'	'	8.13%	8.13%	8.13%

Description_of_Business_and_Su

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Description of Business and Summary of Significant Accounting Policies	'

	1. Description of Business and Summary of Significant Accounting Policies

	Basis of Preparation and Description of Business

	Headquartered in Braintree, Massachusetts, Altra Industrial Motion Corp. (the “Company”), through its wholly-owned subsidiary Altra Power Transmissions, Inc. (“APT”), is a leading multi-national designer, producer and marketer of a wide range of electro-mechanical power transmission products. The Company brings together strong brands covering over 40 product lines with production facilities in eleven countries. Altra’s leading brands include Ameridrives Couplings, Bauer Gear Motor, Bibby Turboflex, Boston Gear, Delroyd Worm Gear, Formsprag Clutch, Huco, Industrial Clutch, Inertia Dynamics, Kilian Manufacturing, Lamiflex Couplings, Marland Clutch, Matrix, Nuttall Gear, Stieber Clutch, Svendborg Brakes, TB Wood’s, Twiflex, Warner Electric, Warner Linear, and Wichita Clutch.

	In November 2013, Altra Holdings, Inc. changed its name to Altra Industrial Motion Corp., and Altra Industrial Motion, Inc., the Company’s wholly owned subsidiary, changed its name to Altra Power Transmission, Inc.

	Principles of Consolidation

	The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

	Net Income Per Share

	Basic earnings per share is based on the weighted average number of common shares outstanding. Diluted earnings per share is based on the weighted average number of common shares outstanding and all dilutive potential common equivalent shares outstanding. Common equivalent shares are included in the per share calculations when the effect of their inclusion would be dilutive.

	The following is a reconciliation of basic to diluted net income per share:



			Year Ended December, 31
			2013			2012			2011
	Net income attributable to Altra Industrial Motion Corp.		$	40,275		$	24,293		$	37,675
	Shares used in net income per common share — basic			26,766			26,656			26,526
	Incremental shares of unvested restricted common stock			75			100			163

	Shares used in net income per common share — diluted			26,841			26,756			26,689
	Earnings per share:
	Basic net income attributable to Altra Industrial Motion Corp.		$	1.5		$	0.91		$	1.42
	Diluted net income attributable to Altra Industrial Motion Corp.		$	1.5		$	0.91		$	1.41

	The Company excluded 3,137,351 shares in 2013, 3,094,706 shares in 2012 and 784,980 shares in 2011 (amounts not in thousands) related to the Convertible Notes (See Note 9) from the above earnings per share calculation as these shares were anti-dilutive.



	Fair Value of Financial Instruments

	The carrying values of financial instruments, including accounts receivable, cash equivalents, accounts payable, and other accrued liabilities are carried at cost, which approximates fair value. Debt under the Company’s Credit Agreement with certain financial institutions including, a Term Loan Facility, as defined below, of $163,245,000 (the “Term Loan Facility”) and a Revolving Credit Facility, as defined below, of $200,000,000 approximate the fair values due to the variable rate nature at current market rates.

	The carrying amount of the 2.75% Convertible Notes (the “Convertible Notes”) was $85.0 million at December 31, 2013 and 2012. The estimated fair value of the Convertible Notes at December 31, 2013 and 2012 was $116.5 million and $94.3 million, respectively, based on inputs other than quoted prices that are observable for the Convertible Notes (level 2).

	Included in cash and cash equivalents as of December 31, 2013 and December 31, 2012 are money market fund investments of $16.6 million and $30.3 million, respectively, which are reported at fair value based on quoted market prices for such investments (level 1).

	The estimated fair value of the Company’s interest rate swap agreement with certain financial institutions (“Interest Rate Swap”) at December 31, 2013 was $0.2 million, based on inputs other than quoted prices that are observable for the Interest Rate Swap (level 2). Inputs include present value of fixed and projected floating rate cash flows over the term of the swap contract. There was no Interest Rate Swap at December 31, 2012.

	Use of Estimates

	The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the financial statements. Actual results could differ from those estimates.

	Non-controlling Interest

	On July 11, 2012, the Company acquired 85% of privately held Lamiflex do Brasil Equipamentos Industriais Ltda. (“Lamiflex”).

	The Company recorded the redeemable non-controlling interest from its acquisition of an 85% ownership interest of Lamiflex at fair value at the date of acquisition. In connection with this acquisition, the Company entered into put and call option agreements with the minority shareholders for the potential purchase of the non-controlling interest at a future date at a value based on a contractually determined formula. As a result of the option agreements, the non-controlling interest is considered redeemable and is classified as temporary equity on the Company’s consolidated balance sheet. The non-controlling interest is reviewed at each subsequent reporting period and adjusted, as needed, to reflect its then redemption value.

	Foreign Currency Translation

	Assets and liabilities of subsidiaries operating outside of the United States with a functional currency other than the U.S. Dollar are translated into U.S. Dollars using exchange rates at the end of the respective period. Revenues and expenses are translated at average exchange rates effective during the respective period.

	Foreign currency translation adjustments are included in accumulated other comprehensive income as a separate component of stockholders’ equity. Net foreign currency transaction gains and losses are included in the results of operations in the period incurred and included in other non-operating expense (income), net in the accompanying statements of comprehensive income.

	Trade Receivables

An allowance for doubtful accounts is recorded for estimated collection losses that will be incurred in the collection of receivables. Estimated losses are based on historical collection experience, as well as a review by management of the status of all receivables. Collection losses have been within the Company’s expectations.



Inventories

Inventories are stated at the lower of cost or market using the first-in, first-out (“FIFO”) method for all entities excluding one of the Company’s subsidiaries, TB Wood’s. TB Wood’s inventory is stated at the lower of cost or market, principally using the last-in, first-out (“LIFO”) method. Inventory stated using the LIFO method approximates 7.5% and 10% of total inventory at December 31, 2013 and 2012, respectively.

The cost of inventories acquired by the Company in its acquisitions reflect their fair values at the date of acquisition as determined by the Company based on the replacement cost of raw materials, the sales price of the finished goods less an appropriate amount representing the expected profitability from selling efforts, and for work-in-process the sales price of the finished goods less an appropriate amount representing the expected profitability from selling efforts and costs to complete.

The Company periodically reviews its quantities of inventories on hand and compares these amounts to the expected usage of each particular product or product line. The Company records a charge to cost of sales for any amounts required to reduce the carrying value of inventories to its estimated net realizable value.

Property, Plant and Equipment

Property, plant and equipment are stated at cost, net of accumulated depreciation.

Depreciation of property, plant and equipment, including capital leases is provided using the straight-line method over the estimated useful life of the asset, as follows:



Buildings and improvements			15 to 45 years
Machinery and equipment			2 to 15 years
Capital lease			Life of lease

Leasehold improvements are depreciated on a straight-line basis over the estimated life of the asset or the life of the lease, if shorter.

Improvements and replacements are capitalized to the extent that they increase the useful economic life or increase the expected economic benefit of the underlying asset. Repairs and maintenance expenditures are charged to expense as incurred.

Intangible Assets

Intangibles represent product technology, patents, tradenames, trademarks and customer relationships. Product technology, patents and customer relationships are amortized on a straight-line basis over 8 to 17 years, which approximates the period of economic benefit. The tradenames and trademarks are considered indefinite-lived assets and are not being amortized. Intangibles are stated at fair value on the date of acquisition. At December 31, 2013 and 2012, intangibles are stated net of accumulated amortization incurred since the date of acquisition and any impairment charges.

Goodwill

Goodwill represents the excess of the purchase price paid by the Company over the fair value of the net assets acquired in each of the Company’s acquisitions.

Impairment of Goodwill and Indefinite-Lived Intangible Assets

The Company conducts an annual impairment review of goodwill and indefinite-lived intangible assets in December of each year, unless events occur which trigger the need for an interim impairment review.

In connection with the Company’s annual impairment review, goodwill is assessed for impairment by comparing the fair value of the reporting unit to the carrying value using a two-step approach. In the first step, the Company estimates future cash flows based upon historical results and current market projections, discounted at a market comparable rate. If the carrying amount of the reporting unit exceeds the estimated fair value, impairment may be present, the Company would then be required to perform a second step in its impairment analysis. In the second step, the Company would evaluate impairment losses based upon the fair value of the underlying assets and liabilities of the reporting unit, including any unrecognized intangible assets, and estimate the implied fair value of the goodwill. An impairment loss is recognized to the extent that a reporting unit’s recorded value of the goodwill asset exceeded its calculated fair value. In addition, to the extent the implied fair value of any indefinite-lived intangible asset is less than the asset’s carrying value, an impairment loss is recognized on those assets. The Company did not identify any impairment of goodwill in 2013, 2012 or 2011.

For our indefinite-lived intangible assets, mainly trademarks, we estimated the fair value first by estimating the total revenue attributable to the trademarks for each of the reporting units. Second, we estimated an appropriate royalty rate using the return on assets method by estimating the required financial return on our

assets, excluding trademarks, less the overall return generated by our total asset base. The return as a percentage of revenue provides an indication of our royalty rate (between 1.0% and 1.5%). We compared the estimated fair value of our trademarks with the carrying value of the trademarks and did not identify any impairment.

Preparation of forecasts of revenue and profitability growth for use in the long-range plan and the discount rate require significant use of judgment. Changes to the discount rate and the forecasted profitability could affect the estimated fair value of one or more of the Company’s reporting units and could result in a goodwill impairment charge in a future period.

Impairment of Long-Lived Assets Other Than Goodwill and Indefinite-Lived Intangible Assets

Long-lived assets, including definite-lived intangible assets, are reviewed for impairment when events or circumstances indicate that the carrying amount of a long-lived asset may not be recovered. Long-lived assets are considered to be impaired if the carrying amount of the asset exceeds the undiscounted future cash flows expected to be generated by the asset over its remaining useful life. If an asset is considered to be impaired, the impairment is measured by the amount by which the carrying amount of the asset exceeds its fair value, and is charged to results of operations at that time.

The Company did not identify any impairment of long-lived assets in 2013 or 2012. In relation to the sale of the Stratford facility in 2011, the Company identified and recorded an impairment with respect to the facility in the amount of $0.1 million based on their fair market value (Note 4).

Determining fair values based on discounted cash flows requires management to make significant estimates and assumptions, including forecasting of revenue and profitability growth for use in the long-range plan and estimating appropriate discount rates. Changes to the discount rate and the forecasted profitability could affect the estimated fair value of one or more of the Company’s indefinite-lived intangible assets and could result in an impairment charge in a future period.

Debt Issuance Costs

Costs directly related to the issuance of debt are capitalized, included in other non-current assets and amortized using the effective interest method over the term of the related debt obligation. The net carrying value of debt issuance costs was approximately $4.1 million and $4.3 million at December 31, 2013 and 2012, respectively.

Revenue Recognition

Product revenues are recognized, net of sales tax collected, at the time title and risk of loss pass to the customer, which generally occurs upon shipment to the customer. Product return reserves are accrued at the time of sale based on the historical relationship between shipments and returns, and are recorded as a reduction of net sales.

Certain large distribution customers receive annual volume discounts, which are estimated at the time the sale is recorded based on the estimated annual sales.

Shipping and Handling Costs

Shipping and handling costs associated with sales are classified as a component of cost of sales.



Warranty Costs

Estimated expenses related to product warranties are accrued at the time products are sold to customers. Estimates are established using historical information as to the nature, frequency, and average costs of warranty claims. See Note 6 to the consolidated financial statements.

Self-Insurance

Certain exposures are self-insured up to pre-determined amounts, above which third-party insurance applies, for medical claims, workers’ compensation, vehicle insurance, product liability costs and general liability exposure. The accompanying balance sheets include reserves for the estimated costs associated with these self-insured risks, based on historic experience factors and management’s estimates for known and anticipated claims. A portion of medical insurance costs are offset by charging employees a premium equivalent to group insurance rates.

Research and Development

Research and development costs are expensed as incurred.

Advertising

Advertising costs are charged to selling, general and administrative expenses as incurred and amounted to approximately $2.5 million, $2.1 million and $1.5 million, for the years ended December 31, 2013, 2012, and 2011, respectively.

Stock-Based Compensation

The Company established the 2004 Equity Incentive Plan, as amended, that provides for various forms of stock-based compensation to officers, directors, key employees and others who make significant contributions to the success of the Company. The Company recognizes stock based compensation expense on a straight line basis for shares vesting ratably under the plan and uses the graded-vesting method of recognizing stock-based compensation expense for performance share awards based on the probability of the specific performance metrics being achieved over the requisite service period.

Income Taxes

The Company records income taxes using the asset and liability method. Deferred income tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax bases, and operating loss and tax credit carryforwards. The Company evaluates the realizability of its net deferred tax assets and assesses the need for a valuation allowance on a quarterly basis. The future benefit to be derived from its deferred tax assets is dependent upon the Company’s ability to generate sufficient future taxable income to realize the assets. The Company records a valuation allowance to reduce its net deferred tax assets to the amount that may be more likely than not to be realized.

To the extent the Company establishes a valuation allowance on net deferred tax assets generated from operations, an expense will be recorded within the provision for income taxes. In periods subsequent to establishing a valuation allowance on net deferred assets from operations, if the Company were to determine that it would be able to realize its net deferred tax assets in excess of their net recorded amount, an adjustment to the valuation allowance would be recorded as a reduction to income tax expense in the period such determination was made.

We assess our income tax positions and record tax benefits for all years subject to examination, based upon our evaluation of the facts, circumstances and information available at the reporting date. For those tax positions for which it is more likely than not that a tax benefit will be sustained, we record the amount that has a greater than 50% likelihood of being realized upon settlement with the taxing authority that has full knowledge of all relevant information. Interest and penalties are accrued, where applicable. If we do not believe that it is more likely than not that a tax benefit will be sustained, no tax benefit is recognized.



Changes in Accumulated Other Comprehensive Loss by Component

The following is a reconciliation of changes in Accumulated Other Comprehensive Loss by Component for the periods presented:



		Cash Flow			Defined			Cumulative			Total
		Hedges			Benefit			Foreign
					Pension Plans			Currency
								Translation
Accumulated Other Comprehensive Loss by Component, January 1, 2012		$	—		$	(2,485	)	$	(22,591	)	$	(25,076	)
Net current-period Other Comprehensive Income Loss			—			(2,122	)		3,795			1,673

Accumulated Other Comprehensive Loss by component, January 1, 2013		$	—		$	(4,607	)	$	(18,796	)	$	(23,403	)

Net current-period Other Comprehensive Income			135			1,474			3,398			5,007

Accumulated Other Comprehensive Income (Loss) by component, December 31, 2013		$	135		$	(3,133	)	$	(15,398	)	$	(18,396	)

Acquisitions

Acquisitions	12 Months Ended
Acquisitions	Dec. 31, 2013
Business Combinations [Abstract]	'
Acquisitions	'

	2. Acquisitions

	In December 2013, the Company consummated an agreement to acquire all of the issued and outstanding shares of Svendborg Brakes A/S and S.B. Patent Holding ApS (together “Svendborg”) for cash consideration of €80.1 million ($110.2 million), less the cash remaining on the balance sheet at close of €5.4 million ($7.5 million). This transaction is referred to as the Svendborg Acquisition. Through the Svendborg Acquisition, the Company acquired the leading global manufacturer of premium quality caliper brakes. With the Svendborg Acquisition, in addition to a presence in Denmark, the Company acquired Denmark’s well-established sales network in 7 additional countries in Western Europe, China, South America, Australia and the United States as well as a manufacturing facility in China.

	Altra financed the transaction through a combination of cash and additional borrowings under its Credit Agreement. Under the Purchase Agreement, the seller agreed to provide the Company with a limited set of representations and warranties, including with respect to outstanding and potential liabilities. Claims for a breach of a representation or warranty are secured by a limited escrow and warranty and indemnity insurance. Damages resulting from a breach of a representation or warranty could have a material and adverse effect on the Company’s financial condition and results of operations, and there is no guarantee that the Company would actually be able to recover all or any portion of the sums payable in connection with such breach.

	Under the Purchase Agreement, the seller agreed to provide the Company with an indemnification for certain tax liabilities related to transfer pricing (the “Transfer Pricing Claims”) identified as part of an ongoing tax audit in Denmark. As part of the Purchase Agreement, an escrow in the amount of approximately €8.5 million ($11.6 million) was established for the Transfer Pricing Claims. The Company estimated this liability to be $8.1 million and as a result has recorded a liability included in taxes payable and an escrow receivable in other current assets. The purchase price in the reconciliation below represents cash consideration less the estimated escrow receivable for which the Company expects to be indemnified.

	The closing date of the Svendborg Acquisition was December 17, 2013, and as a result, the Company’s consolidated financial statements reflect Svendborg’s results of operations from the beginning of business on December 17, 2013 forward.

	As of December 31, 2013, the allocation of the purchase price for the Svendborg Acquisition is preliminary. The fair value of all the acquired identifiable assets and liabilities summarized below is provisional pending finalization of the Company’s acquisition accounting. Measurement period adjustments reflect new information obtained about facts and circumstances that existed as of the acquisition date. The Company believes that such preliminary allocations provide a reasonable basis for estimating the fair values of assets acquired and liabilities assumed, but the Company is waiting for additional information necessary to finalize fair value.



	Purchase price, excluding acquisition costs of approximately $2.5 million		$	102,096
	Cash and cash equivalents			7,483
	Trade receivables, net of amounts pledged			21,575
	Inventories			25,452
	Prepaid and other			5,511
	Property, plant and equipment			12,216
	Other assets			1,133
	Intangible assets			48,893

	Total assets acquired		$	122,263
	Accounts payable			4,833
	Accrued expenses and other current liabilities			9,620
	Taxes payable			10,254
	Deferred tax liability			11,483

	Total liabilities assumed		$	36,190
	Net assets acquired			86,073

	Excess of purchase price over fair value of net assets acquired		$	16,023


	The excess of the purchase price over the fair value of the net assets acquired was recorded as goodwill. This goodwill is not deductible for income tax purposes. The Company expects to develop synergies, such as lower cost country sourcing, global procurement, the ability to cross-sell product, and the ability to penetrate certain geographic areas, as a result of the acquisition of Svendborg.

	The amounts recorded as intangible assets consist of the following:



	Customer relationships, subject to amortization		$	40,050
	Trade names and trademarks, not subject to amortization			8,500
	Patents			343

	Total intangible assets		$	48,893


	Customer relationships are subject to amortization which will be straight-lined over their estimated useful lives of 17 years, which represents the anticipated period over which the Company estimates it will benefit from the acquired assets.

	In July 2012, the Company consummated an agreement to acquire 85% of privately held Lamiflex do Brasil Equipamentos Industrias Ltda. now known as Lamiflex Do Brasil Equipamentos Industriais S.A. This transaction is known as the Lamiflex Acquisition. The Company acquired 85% of the stock of Lamiflex for 17.4 million Reais ($8.6 million), which was subject to a reduction of 2.1 million Reais ($1.1 million) for estimated net debt at closing.

	The closing date of the Lamiflex Acquisition was July 11, 2012, and as a result, the Company’s consolidated financial statements reflect Lamiflex’s results of operations from the beginning of business on July 11, 2012 forward.

	The Company has completed the valuation of customer relationships, trademarks and deferred tax assets and liabilities and fixed assets and has recorded them as part of its balance sheet. The purchase price allocation was calculated as if the Company had acquired 100% of Lamiflex. The purchase price allocation as of the acquisition date is as follows:



	Total Assumed purchase price, excluding acquisition costs of approximately $0.4 million		$	8,820
	Less: Redeemable noncontrolling interest			1,327

	Total purchase price paid at closing			7,493
Cash and cash equivalents			68
Trade receivables, net of amounts pledged			606
Inventories			726
Prepaid and other			48
Property, plant and equipment			3,027
Other assets			108
Intangible assets			4,912

Total assets acquired		$	9,495
Accounts payable			550
Accrued expenses and other current liabilities			867
Deferred tax liability			1,934
Other liabilities, including long-term debt			976

Total liabilities assumed		$	4,327
Net assets acquired			5,168

Excess of purchase price over fair value of net assets acquired			3,652


The excess of the purchase price over the fair value of the net assets acquired was recorded as goodwill. This goodwill is deductible for income tax purposes. The Company expects to develop synergies, such as the ability to cross-sell product and to penetrate into certain geographic areas, as a result of the acquisition of Lamiflex.

The Company recorded a redeemable non-controlling interest from its acquisition of an 85% ownership interest of Lamiflex at fair value at the date of acquisition. In connection with the Lamiflex Acquisition, the Company entered into put and call option agreements with the minority shareholders for the potential purchase of the non-controlling interest at a future date at a value based on a contractually determined formula. As a result of the option agreements, the non-controlling interest is considered redeemable and is classified as temporary equity on the Company’s Consolidated Balance Sheet.

The estimated amounts recorded as intangible assets in connection with the Lamiflex Acquisition consist of the following:



Customer relationships, subject to amortization		$	4,552
Trade names and trademarks, not subject to amortization			360

Total intangible assets		$	4,912


Customer relationships are subject to amortization which will be straight-lined over their estimated useful lives of 13 years, which represents the anticipated period over which the Company estimates it will benefit from the acquired assets.

The following table sets forth the unaudited pro forma results of operations of the Company for the year to date periods ended December 31, 2013, 2012 and 2011 as if the Company had acquired Lamiflex and Bauer at January 1, 2011, and Svendborg at January 1, 2012. The pro forma information contains the actual operating results of the Company, including Bauer, Lamiflex, and Svendborg adjusted to include the pro forma impact of (i) additional depreciation expense as a result of estimated depreciation based on the fair value of fixed assets; (ii) additional expense as a result of the estimated amortization of identifiable intangible assets (iii) additional interest expense associated with the Convertible Notes issued on March 7, 2011 in connection with the Bauer Acquisition; (iv) elimination of certain acquisition related costs; (v) the elimination of additional expense as a result of fair value adjustment to inventory recorded in connection with the Lamiflex and Bauer Acquisitions; and (vi) additional interest expense for borrowings under the Credit Agreement associated with the Svendborg Acquisition. These pro forma amounts do not purport to be indicative of the results that would have actually been obtained if the acquisition occurred at the beginning of the period or that may be obtained in the future.



		2013			2012		2011
Total revenues		$	803,467		$	818,956	$	732,837
Net income attributable to Altra Industrial Motion Corp.		$	37,750		$	22,373	$	41,718
Basic earnings per share:
Net income attributable to Altra Industrial Motion Corp.		$	1.41		$	0.84	$	1.57
Diluted earnings per share:
Net income attributable to Altra Industrial Motion Corp.		$	1.41		$	0.84	$	1.56

Inventories

Inventories	12 Months Ended
Inventories	Dec. 31, 2013
Inventory Disclosure [Abstract]	'
Inventories	'

	3. Inventories

	Inventories are generally stated at the lower of cost or market, using the first-in, first-out (“FIFO”) method. Inventories located at certain subsidiaries acquired in connection with the TB Wood’s acquisition are stated at the lower of current cost or market, principally using the last-in, first-out (LIFO) method. The cost of inventory includes direct materials, direct labor, and production overhead. Market is defined as net realizable value. Inventories at December 31, 2013 and 2012 consisted of the following:



		December 31,		December 31,
		2013		2012
	Raw materials	$	56,824	$	39,902
	Work in process		18,432		21,199
	Finished goods		68,409		62,675

	Inventories, net	$	143,665	$	123,776


	Approximately 7.5% of total inventories at December 31, 2013, were valued using the LIFO method. The Company recorded as a component of cost of sales, a $0.7 million, and a $0.4 million provision in the years ended December 31, 2013 and 2012, respectively. If the LIFO inventory was accounted for using the FIFO method, the inventory balance at December 31, 2013 and 2012, would be $1.6 million higher and $0.9 million higher, respectively.

Property_Plant_and_Equipment

Property, Plant and Equipment	12 Months Ended
Property, Plant and Equipment	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Property, Plant and Equipment	'

	4. Property, Plant and Equipment

	Property, plant and equipment at December 31, 2013 and 2012, consisted of the following:



		2013			2012
	Land	$	20,803		$	13,565
	Buildings and improvements		53,078			38,942
	Machinery and equipment		207,193			190,809

			281,074			243,316
	Less-Accumulated depreciation		(123,539	)		(105,222	)

		$	157,535		$	138,094


	In 2011, the Company sold its Stratford, Ontario, Canada facility for approximately $0.9 million. Cash was received for $0.3 million and a note receivable was established for $0.6 million, which has a term of 10 years and accrues interest at 6% annually. In 2013, the note receivable was paid in full.

	In 2013, the Company sold its Mt. Pleasant, Michigan facility and received cash consideration of approximately $0.6 million. The cash consideration was equal to the net book value and therefore no impairment was recorded.

	The Company recorded $21.4 million, $20.5 million and $18.4 million of depreciation expense in the years ended December 31, 2013, 2012, and 2011, respectively.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	12 Months Ended
Goodwill and Intangible Assets	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets	'

	5. Goodwill and Intangible Assets

	Changes in goodwill during the year ended December 31, 2013 and 2012 were as follows:



		2013			2012
	Gross goodwill balance as of January 1	$	120,035		$	115,609
	Adjustments related to the acquisition of Svendborg in 2013 and Lamiflex in 2012		16,023			3,652
	Impact of changes in foreign currency and other		91			774

	Gross goodwill balance as of December 31		136,149			120,035

	Accumulated impairment, January 1		(31,810	)		(31,810	)
	Impairment charge during period		—			—
	Accumulated impairment, December 31		(31,810	)		(31,810	)

	Net goodwill balance December 31	$	104,339		$	88,225




	Intangibles and related accumulated amortization consisted of the following:



		December 31, 2013						December 31, 2012
		Cost			Accumulated			Cost			Accumulated
		Cost			Amortization			Cost			Amortization
	Intangible Assets
	Intangible assets not subject to amortization:
	Tradenames and trademarks	$	42,985		$	—		$	34,485		$	—
	Intangible assets subject to amortization:
	Customer relationships		118,914			42,645			78,864			36,202
	Product technology and patents		6,062			5,719			5,719			5,657
	Impact of changes in foreign currency		(829	)		—			(1,111	)		—

	Total intangible assets	$	167,132		$	48,364		$	117,957		$	41,859


	The Company recorded $6.5 million, $6.8 million, and $6.3 million of amortization for the years ended December 31, 2013, 2012 and 2011, respectively.

	Customer relationships, product technology and patents are amortized over their useful lives ranging from 8 to 17 years. The weighted average estimated useful life of intangible assets subject to amortization is approximately 11 years.

	The estimated amortization expense for intangible assets is approximately $8.8 million in 2014, $8.8 million in each of the next four years and then $31.8 million thereafter.

Warranty_Costs

Warranty Costs	12 Months Ended
Warranty Costs	Dec. 31, 2013
Guarantees [Abstract]	'
Warranty Costs	'

	6. Warranty Costs

	The Company’s wholly owned subsidiaries manufacture various products. The contractual warranty period generally ranges from three months to two years with certain warranties extending for longer periods based on the product and application of the product. Estimated expenses related to product warranties are accrued at the time products are sold to customers and are recorded in accruals and other current liabilities on the consolidated balance sheet. Estimates are established using historical information as to the nature, frequency and average costs of warranty claims. Changes in the carrying amount of accrued product warranty costs for each of the years ended December 31, 2013, 2012, and 2011 are as follows:



		December 31,			December 31,			December 31,
		2013			2012			2011
	Balance at beginning of period	$	5,625		$	4,898		$	3,583
	Accrued current period warranty costs		2,573			2,386			2,374
	Acquired warranty reserves		3,420			—			1,720
	Payments and adjustments		(2,879	)		(1,659	)		(2,779	)

	Balance at end of period	$	8,739		$	5,625		$	4,898

Income_Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'

	7. Income Taxes

	Income before income taxes by domestic and foreign locations consists of the following:



			December 31,				December 31,				December 31,
			2013				2012				2011
	Domestic		$	37,640			$	18,083			$	34,034
	Foreign			21,696				16,276				14,397

	Total		$	59,336			$	34,359			$	48,431


	The components of the provision (benefit) for income taxes consist of the following:



			December 31,				December 31,				December 31,
			2013				2012				2011
	Current:
	Federal		$	8,917			$	8,370			$	4,506
	State			698				(3,597	)			(3,686	)
	Non-US			6,072				6,006				5,057

			$	15,687			$	10,779			$	5,877

	Deferred:
	Federal		$	3,533			$	(915	)		$	7,949
	State			378				1,756				(861	)
	Non-US			(447	)			(1,466	)			(2,209	)

				3,464				(625	)			4,879

	Provision (benefit) for income taxes		$	19,151			$	10,154			$	10,756


	A reconciliation from tax at the U.S. federal statutory rate to the Company’s provision (benefit) for income taxes is as follows:



			December 31,				December 31,				December 31,
			2013				2012				2011
	Tax at US federal income tax rate		$	20,767			$	12,026			$	16,957
	State taxes, net of federal income tax effect			905				67				1,050
	Change in tax rate			(354	)			(267	)			(236	)
	Foreign taxes			(224	)			781				709
	Adjustments to accrued income tax liabilities and uncertain tax positions			(52	)			(1,289	)			(3,413	)
	Valuation allowance			120				506				(1,644	)
	Intercompany interest			(986	)			(1,676	)			(1,178	)
	Tax credits and incentives			(816	)			(291	)			(1,243	)
	Domestic Manufacturing Deduction			(839	)			(566	)			(544	)
	Other			630				863				298

	Provision (benefit) for income taxes		$	19,151			$	10,154			$	10,756


	The Company and its subsidiaries file a consolidated federal income tax return in the United States, as well as consolidated and separate income tax returns in various states. The Company and its subsidiaries also file consolidated and separate income tax returns in various non-U.S. jurisdictions. In the normal course of business, the Company is subject to examination by taxing authorities in all of these jurisdictions. With the exception of certain foreign jurisdictions, the Company is no longer subject to income tax examinations for the tax years prior to 2010. Svendborg is currently subject to an audit in Denmark for the years 2007-2011. As set forth in Note 2 above, the seller agreed to provide the Company with an indemnification for certain tax liabilities related to transfer pricing (the “Transfer Pricing Claims”) identified as part of the audit in Denmark. As part of the Purchase Agreement, an escrow in the amount of approximately €8.5 million ($11.6 million) was established for the Transfer Pricing Claims. The Company estimated this liability to be $8.1 million and as a result has recorded a liability in taxes payable. Additionally, the Company has indemnification agreements with the sellers of the Colfax PTH, Kilian, Bauer, Svendborg, and Hay Hall entities that provide for reimbursement to the Company for payments made in satisfaction of tax liabilities relating to pre-acquisition periods.

	A reconciliation of the gross amount of unrecognized tax benefits excluding accrued interest and penalties is as follows:



		December 31,				December 31,				December 31,
		2013				2012				2011
Balance at beginning of period		$	747			$	3,523			$	6,338
Increases related to prior year tax positions			—				—				—
Decreases related to prior year tax positions			(33	)			—				(2,289	)
Increases related to current year tax positions			—				—				—
Settlements			—				(2,689	)			—
Lapse of statute of limitations			(87	)			(87	)			(526	)

Balance at end of period		$	627			$	747			$	3,523


In 2012, the Company recognized a $2.5 million tax benefit for the reduction of the Company’s reserve for uncertain tax positions due to a settlement with the State of New York for which the Company was fully indemnified.

In 2011, the Company recognized a tax benefit for the reduction of the Company’s reserve for uncertain tax positions due to a favorable New Jersey Supreme Court ruling in a case that did not involve the Company. The reserve consisted of approximately $2.3 million of tax, $1.8 million of accrued interest and $0.5 million of penalties. In addition, the Company reversed $1.4 million of deferred tax assets related to the federal benefit of the accrued state reserve. The net benefit to the Company was approximately $3.2 million

The Company recognizes interest and penalties related to unrecognized tax benefits in income tax expense in the Consolidated Statement of Comprehensive Income. The Company accrued interest and penalties of $0.1 million (off-set by a $0.1 million benefit of interest and penalties primarily related to the lapse of the applicable statute of limitations), $0.2 million, and $0.6 million during the years ended December 31, 2013, 2012 and 2011, respectively. The total gross amount of interest and penalties related to uncertain tax positions at December 31, 2013, 2012, and 2011 was $0.4 million, $0.4 million, $2.7 million, respectively. Although it is reasonably possible that a change in the balance of unrecognized tax benefits might occur within the next twelve months, at this time it is not possible to estimate the range of change due to the uncertainty of the potential outcomes.

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes.



Significant components of the deferred tax assets and liabilities as of December 31, 2013 and 2012 are as follows:



		2013				2012
Deferred tax assets:
Post-retirement obligations		$	1,565			$	3,157
Tax credits			2,165				2,040
Expenses not currently deductible			11,788				11,598
Net operating loss carryover			6,376				6,435
Other			546				790

Total deferred tax assets			22,440				24,020
Valuation allowance for deferred tax assets			(5,577	)			(5,426	)

Net deferred tax assets			16,863				18,594
Deferred tax liabilities:
Property, plant and equipment			20,065				19,892
Intangible assets			25,090				14,969
Basis difference - convertible debt			11,064				10,212
Goodwill			3,813				2,308

Total deferred liabilities			60,032				47,381

Net deferred tax liabilities		$	43,169			$	28,787


On December 31, 2013 the Company had state net operating loss (NOL) carry forwards of $28.1 million, which expire between 2018 and 2032, and non U.S. NOL carryforwards of $22.7 million, of which substantially all have an unlimited carryforward period. The NOL carryforwards available are subject to limitations on their annual usage. The Company also has federal and state tax credits of $2.4 million available to reduce future income taxes that expire between 2014 and 2028.

Valuation allowances are established for deferred tax assets that management believes may not be realized. The Company continually reviews the adequacy of its valuation allowances and recognizes tax benefits only as reassessments indicate that it is more likely than not the benefits will be realized. Valuation allowances of $5.6 million and $5.4 million as of December 31, 2013 and December 31, 2012, respectively, have been established due to the uncertainty of realizing the benefits of certain net operating losses, tax credits, and other tax attributes. The valuation allowances are primarily related to certain non-U.S. NOL carryforwards, capital loss carryforwards, and U.S. federal foreign tax credits.

A provision has not been made for U.S. or additional non-U.S. taxes on $59.9 million of undistributed earnings of international subsidiaries that could be subject to taxation if remitted to the U.S. because the Company plans to keep these amounts permanently reinvested outside the U.S. except for instances where the Company has already been subject to tax in the U.S. It is not practicable to determine the amount of deferred income taxes not provided on these earnings.

Pension_and_Other_Employee_Ben

Pension and Other Employee Benefits	12 Months Ended
Pension and Other Employee Benefits	Dec. 31, 2013
Compensation And Retirement Disclosure [Abstract]	'
Pension and Other Employee Benefits	'

	8. Pension and Other Employee Benefits

	Defined Benefit (Pension)

	The Company sponsors various defined benefit (pension) plans for certain, primarily unionized, active employees (those in the employment of the Company at, and certain employees hired since, November 30, 2004).



	The following tables represent the reconciliation of the benefit obligation, fair value of plan assets and funded status of the respective defined benefit (pension) plans as of December 31, 2013 and 2012:



			Pension Benefits
			Year Ended				Year Ended
			December 31,				December 31,
			2013				2012
	Change in benefit obligation:
	Obligation at beginning of period		$	34,629			$	29,415
	Assumed Bauer pension liability			—				—
	Service cost			248				179
	Interest cost			1,250				1,381
	Curtailments, settlements and special termination benefits			—				—
	Actuarial (gains) losses			(2,969	)			4,574
	Foreign exchange effect			343				153
	Benefits paid			(1,286	)			(1,073	)

	Obligation at end of period		$	32,215			$	34,629

	Change in plan assets:
	Fair value of plan assets, beginning of period		$	20,100			$	16,519
	Assumed Bauer plan assets			—				—
	Actual return on plan assets			182				2,035
	Employer contributions			5,194				2,619
	Benefits paid			(1,286	)			(1,073	)

	Fair value of plan assets, end of period		$	24,190			$	20,100

	Funded status		$	(8,025	)		$	(14,529	)

	Amounts Recognized in the balance sheet consist of:
	Non current assets		$	—			$	—
	Current liabilities			—				—
	Non-current liabilities			(8,025	)			(14,529	)

	Total		$	(8,025	)		$	(14,529	)


	For all pension plans presented above, the accumulated and projected benefit obligations exceed the fair value of plan assets. The accumulated benefit obligation at December 31, 2013 and 2012 was $32.2 million and $34.6 million, respectively. Non-U.S. pension liabilities recognized in the amounts presented above are $7.7 million and $7.6 million at December 31, 2013 and 2012, respectively.

	Included in accumulated other comprehensive loss at December 31, 2013 and 2012, is $1.5 million (net of $0.8 million in taxes) and $2.1 million (net of $1.4 million in taxes), respectively, of unrecognized actuarial losses that have not yet been recognized in net periodic pension cost.

	The discount rate used in the computation of the respective benefit obligations at December 31, 2013 and 2012, presented above are as follows:



			2013				2012
	Pension benefits			4.6	%			3.75	%



	The following table represents the components of the net periodic benefit cost associated with the respective plans:



		Pension Benefits
		Year Ended				Year Ended				Year Ended
		December 31,				December 31,				December 31,
		2013				2012				2011
Service cost		$	248			$	179			$	167
Interest cost			1,250				1,381				1,389
Recognized net actuarial loss			—				—				—
Expected return on plan assets			(1,080	)			(1,083	)			(1,050	)
Settlement/Curtailment/			—				—				—
Special Termination Benefit			—				—				—
Amortization			175				105				39

Net periodic benefit (income) cost		$	593			$	582			$	545


The key economic assumptions used in the computation of the respective net periodic benefit cost for the periods presented above are as follows:



		Pension Benefits
		Year Ended				Year Ended				Year Ended
		December 31,				December 31,				December 31,
		2013				2012				2011
Discount rate			3.75	%			4.75	%			5.5	%
Expected return on plan assets			5.25	%			6.25	%			7.75	%
Compensation rate increase			N/A				N/A				N/A

The expected long-term rate of return on assets assumption is 5.25%. The assumption represents the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. The assumption reflects expectations regarding future rates of return for the investment portfolio, with consideration given to the distribution of investments by asset class and historical rates of return for each individual asset class.



Fair Value of Plan Assets

The fair value of the Company’s pension plan assets at December 31, 2013 and 2012 by asset category is as follows:



			2013				2012
Asset Category
Equity (Level 1)
U.S. companies		$	—			$	4,522
International companies			—				297

Total equity			—				4,819
Fixed income (Level 1)
U.S. government			2,787				820
Corporate bonds
Investment grade			17,091				8,738
High yield			3,634				3,151
Other credit			—				1,632

Total fixed income			23,512				14,341
Other (Level 2)			338				328
Cash and cash equivalents (Level 1)			340				612

Total assets at fair value		$	24,190			$	20,100


The asset allocations for the Company’s funded retirement plan at December 31, 2013 and 2012, respectively, and the target allocation for 2013, by asset category, are as follows:



		Allocation Percentage of
		Plan Assets at Year-End
		2013				2013		2012
		Actual				Target		Actual
Asset Category
Global Developed Equity			0	%		0%			5	%
Investment Grade Bonds			84	%		20% - 100%			48	%
High Yield Bonds			15	%		0% - 25%			16	%
Cash			1	%		0% - 5%			3	%
Emerging Market Debt			0	%		0%			3	%
Dynamic Asset Allocation/Alternatives			0	%		0%			25	%

The investment strategy is to achieve a rate of return on the plan’s assets that meets the performance of liabilities as calculated using a bank’s Liability Index with appropriate adjustments for benefit payments, service cost and actuarial assumption changes. A determinant of the plan’s return is the asset allocation policy. The plan’s asset mix will be reviewed by the Company periodically, but at least quarterly, to rebalance within the target guidelines. The Company will also periodically review investment managers to determine if the respective manager has performed satisfactorily when compared to the defined objectives, similarly invested portfolios, and specific market indices.

Expected cash flows

The following table provides the amounts of expected benefit payments, which are made from the plans’ assets and includes the participants’ share of the costs, which is funded by participant contributions. The amounts in the table are actuarially determined and reflect the Company’s best estimate given its current knowledge; actual amounts could be materially different.



		Pension
		Benefits
Expected benefit payments (from plan assets)
2014			1,153
2015			1,309
2016			1,370
2017			1,399
2018			1,464
Thereafter			7,895

The Company contributed $5.0 million to its U.S. pension plan in 2013. The Company has no minimum cash funding requirements associated with its pension plans for years 2014 and 2015, and $0.3 million for years 2016 through 2018.

Post Retirement Benefit Plans

Certain, primarily unionized, employees are entities to limited grandfathered postretirement benefits (medical, dental, and life insurance coverage). The accumulated benefit obligation for the post-retirement benefit plans, which are not funded, at December 31, 2013 and 2012 are $0.2 million and $0.2 million respectively. The balances are included within other long-term liabilities on the consolidated balance sheet. The Company recorded less than $0.1 million of income for of the years ended December 31, 2013, 2012 and 2011.

Defined Contribution Plans

Under the terms of the Company’s defined contribution plans, eligible employees may contribute up to seventy-five percent of their compensation to the plan on a pre-tax basis, subject to annual IRS limitations. The Company makes matching contributions equal to half of the first six percent of salary contributed by each employee and made a unilateral contribution (including for non-contributing employees). The Company’s expense associated with the defined contribution plans was $3.7 million and $3.5 million during the years ended December 31, 2013 and 2012, respectively.

LongTerm_Debt

Long-Term Debt	12 Months Ended
Long-Term Debt	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Long-Term Debt	'

	9. Long-Term Debt



			December 31,			December 31,
			2013			2012
	Debt:
	Revolving Credit Facility		$	41,198		$	79,304
	Convertible Notes			85,000			85,000
	Term Loan Facility			163,245			100,000
	Equipment Loan			4,155			1,100
	Mortgages			659			963
	Capital leases			178			99
	Other			—			435
	Total debt			294,435			266,901
	Less: debt discount, net of accretion			(16,163	)		(19,306	)

	Total debt, net of unaccreted discount		$	278,272		$	247,595

	Less current portion of long-term debt			16,924			9,135

	Total long-term debt		$	261,348		$	238,460


	Credit Agreement

	In December 2013, the Company entered into an Amended and Restated Credit Agreement (the “Credit Agreement”). The Credit Agreement amends and restates the Company’s Former Credit Agreement, dated November 20, 2012. Pursuant to the Former Credit Agreement, the former lenders made available to the Company an initial term loan facility of $100,000,000 and an initial "Revolving Credit Facility" of $200,000,000.

	Pursuant to the Credit Agreement, the lenders made an additional term loan of €50,000,000 (the “Additional Term Loan”) to Altra Industrial Motion Netherlands B.V. The Credit Agreement keeps in effect the balance (approximately $94,375,000) of the existing term loan facility (the “Initial Term Loan”) made to the domestic borrowers under the Former Credit Agreement (collectively, the two term loans are referred to as the “Term Loan Facility”), as well as the revolving credit facility of $200,000,000 made under the Former Credit Agreement (the “Revolving Credit Facility”). The Credit Agreement continues, even after the making of the Additional Term Loan, to provide for a possible expansion of the credit facilities by an additional $150,000,000, which can be allocated as additional term loans and/or additional revolving credit loans. The amounts available under the Term Loan Facility were used, and amounts available under the Revolving Credit Facility can be used, for general corporate purposes, including acquisitions, and to repay existing indebtedness. The stated maturity of these credit facilities is December 6, 2018, and there are scheduled quarterly principal payments due on the outstanding amount of the Term Loan Facility. With respect to the Initial Term Loan, the scheduled quarterly principal payments due on the outstanding amount have been reamortized in accordance with the new December 6, 2018 maturity date. The previous maturity of the Revolving Credit Facility and the Initial Term Loan was November 20, 2017.

	The amounts available under the Revolving Credit Facility may be drawn upon in accordance with the terms of the Credit Agreement. All amounts outstanding under the credit facilities are due on the stated maturity or such earlier time, if any, required under the Credit Agreement. The amounts owed under either of the credit facilities may be prepaid at any time, subject to usual notification and breakage payment provisions. Interest on the amounts outstanding under the credit facilities is calculated using either an ABR Rate or Eurodollar Rate, plus the applicable margin. The applicable margins for Eurodollar Loans are between 1.375% to 1.875%, and for ABR Loans are between 0.375% and 0.875%. The amounts of the margins are calculated based on either a consolidated total net leverage ratio (as defined in the Credit Agreement), or the then applicable rating(s) of the Company’s debt if and then to the extent as provided in the Credit Agreement. A portion of the Revolving Credit Facility may also be used for the issuance of letters of credit, and a portion of the amount of the Revolving Credit Facility is available for borrowings in certain agreed upon foreign currencies.

	As of December 31, 2013 and 2012, we had $41.2 million and $79.3 million outstanding on our Revolving Credit Facility, respectively. As of December 31, 2013 and 2012, we had $9.8 and $7.6 million in letters of credit outstanding, respectively. We had $149.0 million and $113.1 million available under the Revolving Credit Facility at December 31, 2013 and 2012, respectively.

	The Credit Agreement contains various affirmative and negative covenants and restrictions, which among other things, will require the Company and certain Subsidiaries to provide certain financial reports to the Lenders, require the Company to maintain certain financial covenants relating to consolidated leverage and interest coverage, limit maximum annual capital expenditures, and limit the ability of the Company and its subsidiaries to incur or guarantee additional indebtedness, pay dividends or make other equity distributions, purchase or redeem capital stock or debt stock or debt, make certain investments, sell assets, engage in certain transactions, and effect a consolidation or merger. The Credit Agreement also contains customary events of default.

	Former Credit Agreement

	In November 2012, the Company entered into a Credit Agreement (the “Former Credit Agreement”) with certain financial institutions (collectively, the “Lenders”), to be guaranteed by certain domestic subsidiaries of the Company (each a “Guarantor” and collectively the “Guarantors”). Pursuant to the Former Credit Agreement, the Lenders made available to the Company an initial term loan facility of $100,000,000 (the “Term Loan Facility”) and an initial revolving credit facility of $200,000,000 (the “Revolving Credit Facility”).

	Interest on the amounts outstanding under the credit facilities is calculated using either an ABR Rate or Eurodollar rate, plus the applicable margin. The applicable margins for Eurodollar Loans are between 1.375% to 1.875%, and for ABR Loans are between 0.375% and 0.875%. The Credit Agreement provides for a possible expansion of the facilities by an aggregate additional $150,000,000, which can be allocated as additional term loans and/or additional revolving credit loans. The amounts available under the Former Credit Agreement were to be available for general corporate purposes and to repay indebtedness. Under the Former Credit Agreement, the stated maturity of both of these credit facilities was November 20, 2017. A portion of the Revolving Credit Facility may be used for the issuance of letters of credit, and a portion of the amount of the Revolving Credit Facility is available for borrowings in certain agreed upon foreign currencies.

	The proceeds of the Term Loan Facility and a portion of the proceeds of the Revolving Credit Facility, along with cash on hand, were used by the Company to contribute all funds necessary to redeem all of the Company’s Senior Secured Notes in December 2012 (the “Redemption”). As of December 31, 2012, we had $79.3 million outstanding on our Revolving Credit Facility, $7.6 million in letters of credit outstanding, and $113.1 million available under the Revolving Credit Facility.

	The Former Credit Agreement contained various affirmative and negative covenants and restrictions, which are largely identical to those of the Credit Agreement. The Company was in compliance in all material respects with all material covenants of the Credit Agreement at December 31, 2012.

	Pledge and Security Agreement; Trademark Security Agreement; Patent Security Agreement.

	Pursuant to an Omnibus Reaffirmation and Ratification of Collateral Documents entered into on December 6, 2013 in connection with the Credit Agreement by and among the Company, the Loan Parties and the Administrative Agent (the “Ratification Agreement”), the Loan Parties (exclusive of the foreign subsidiary Borrower) have reaffirmed their obligations to the Lenders under the Pledge and Security Agreement The Credit Agreement provides that the obligation to grant the security interest can cease upon the obtaining of certain corporate family credit ratings for the Company, but the obligation to grant a security interest is subject to subsequent reinstatement if the ratings are not maintained as provided in the Credit Agreement.

	Pursuant to the Ratification Agreement, the Loan Parties (other than the foregoing subsidiary Borrower) have also reaffirmed their obligations under each of the Patent Security Agreement and a Trademark Security Agreement.



	Pursuant to the Former Credit Agreement, on November 20, 2012, the Loan Parties and the Administrative Agent entered into a Pledge and Security Agreement (the “Pledge and Security Agreement”), pursuant to which each Loan Party pledges, assigns and grants to the Administrative Agent, on behalf of and for the ratable benefit of the Lenders, a security interest in all of its right, title and interest in, to and under all personal property, whether now owned by or owing to, or after acquired by or arising in favor of such Loan Party (including under any trade name or derivations), and whether owned or consigned by or to, or leased from or to, such Loan Party, and regardless of where located, except for specific excluded personal property identified in the Pledge and Security Agreement (collectively, the “Collateral”). Notwithstanding the foregoing, the Collateral does not include, among other items, more than 65% of the capital stock of the first tier foreign subsidiaries of the Company. The Pledge and Security Agreement contains other customary representations, warranties and covenants of the parties. The Credit Agreement provides that the obligation to grant the security interest can cease upon the obtaining of certain corporate family ratings for the Company, but the obligation to grant a security interest is subject to subsequent reinstatement if the ratings are not maintained as provided in the Credit Agreement.

	In connection with the Pledge and Security Agreement, certain of the Loan Parties delivered a Patent Security Agreement and a Trademark Security Agreement in favor of the Administrative Agent pursuant to which each of the Loan Parties signatory thereto pledges, assigns and grants to the Administrative Agent, on behalf of and for the ratable benefit of the Lenders, a security interest in all of its right, title and interest in, to and under all registered patents, patent applications, registered trademarks and trademark applications owned by such Loan Parties.

	Convertible Senior Notes

	In March 2011, the Company issued Convertible Senior Notes (the “Convertible Notes”) due March 1, 2031. The Convertible Notes are guaranteed by the Company’s U.S. domestic subsidiaries. Interest on the Convertible Notes is payable semi-annually in arrears, on March 1 and September 1 of each year, commencing on September 1, 2011 at an annual rate of 2.75%. Proceeds from the offering were $81.3 million, net of fees and expenses that were capitalized. The proceeds from the offering were used to fund the Bauer Acquisition, as well as bolster the Company’s cash position.

The Convertible Notes will mature on March 1, 2031, unless earlier redeemed, repurchased by the Company or converted, and are convertible into cash or shares, or a combination thereof, at the Company’s election. The Convertible Notes are convertible into shares of the Company’s common stock based on an initial conversion rate, subject to adjustment, of 36.0985 shares per $1,000 principal amount of notes (which represents an initial conversion price of approximately $27.70 per share of our common stock), in certain circumstances. The conversion price at December 31, 2013 is $27.09 per share. Prior to March 1, 2030, the Convertible Notes are convertible only in the following circumstances: (1) during any fiscal quarter commencing after June 30, 2011 if the last reported sale price of the Company’s common stock is greater than or equal to 130% of the applicable conversion price for at least 20 trading days in the period of 30 consecutive trading days ending on the last trading day of the preceding fiscal quarter; (2) during the five business day period after any 10 consecutive trading day period (the “measurement period”) in which the trading price per $1,000 principal amount of notes for each trading day in the measurement period was less than 97% of the product of the last reported sale price of the Company’s common stock and the conversion rate on such trading day; (3) if the Convertible Notes have been called for redemption; or (4) upon the occurrence of specified corporate transactions. On or after March 1, 2030, and ending at the close of business on the second business day immediately preceding the maturity date, holders may convert their Convertible Notes at any time, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of common stock, or a combination thereof, at the Company’s election. The Company intends to settle the principal amount in cash and any additional amounts in shares of stock.

If a fundamental change occurs, the Convertible Notes are redeemable at a price equal to 100% of the principal amount of the notes to be repurchased, plus accrued and unpaid interest (including contingent interest and additional interest, if any) to, but excluding, the repurchase date. The Convertible Notes are also redeemable on each of March 1, 2018, March 1, 2021, and March 1, 2026 for cash at a price equal to 100% of the principal amount of the notes to be repurchased, plus accrued and unpaid interest (including contingent interest and additional interest, if any) to, but excluding, the option repurchase date.

On or after March 1, 2015, the Company may call all or part of the Convertible Notes at a redemption price equal to 100% of the principal amount of the Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date, plus a “make-whole premium” payment in cash, shares of the Company’s common stock, or combination thereof, at the Company’s option, equal to the sum of the present values of the remaining scheduled payments of interest on the Convertible Notes to be redeemed through March 1, 2018 to, but excluding, the redemption date, if the last reported sale price of the Company’s common stock for 20 or more trading days in a period of 30 consecutive trading days ending on the trading day prior to the date the Company provides notice of redemption exceeds 130% of the conversion price in effect on each such trading day. On or after March 1, 2018, the Company may redeem for cash all or a portion of the notes at a redemption price of 100% of the principle amount of the Convertible Notes to be redeemed, plus accrued and unpaid interest (including contingent and additional interest, if any) to, but not including, the redemption date.

The Company separately accounted for the debt and equity components of the Convertible Notes to reflect the issuer’s non-convertible debt borrowing rate, which interest costs are to be recognized in subsequent periods. The note payable principal balance at the date of issuance of $85.0 million was bifurcated into a debt component of $60.5 million and an equity component of $24.5 million. The difference between the note payable principal balance and the value of the debt component is being accreted to interest expense over the term of the notes. The debt component was recognized at the present value of associated cash flows discounted using a 8.25% discount rate, the borrowing rate at the date of issuance for a similar debt instrument without a conversion feature. The Company paid approximately $3.7 million of issuance costs associated with the Convertible Notes. The Company recorded $1.0 million of debt issuance costs as an offset to additional paid-in capital. The balance of $2.7 million of debt issuance costs is classified as other non-current assets and will be amortized over the term of the notes using the effective interest method.

The carrying amount of the principal amount of the liability component, the unamortized discount, and the net carrying amount are as follows as of December 31, 2013:



		December 31,
		2013
Principal amount of debt		$	85,000
Unamortized discount			16,163

Carrying value of debt		$	68,837


Interest expense associated with the Convertible Notes consisted of the following for the year ended December 31, 2013:



		December 31,
		2012
Contractual coupon rate of interest		$	2,338
Accretion of Convertible Notes discount and amortization of deferred financing costs			3,494

Interest expense for the Convertible Notes		$	5,832


The effective interest yield of the Convertible Notes due in 2031 is 8.5% at December 31, 2013 and the cash coupon interest rate is 2.75%.

Senior Secured Notes

In November 2009, the Company issued 8 1/8% Senior Secured Notes (the “Senior Secured Notes”) with a face value of $210 million. Interest on the Senior Secured Notes was payable semi-annually in arrears, on June 1 and December 1 of each year, commencing on June 1, 2010 at an annual rate of 8 1/8%. The effective interest rate of the Senior Secured Notes was approximately 8.75% after consideration of the $6.7 million of deferred financing costs (included in other non-current assets which are being amortized over the term using the effective interest method). The principal balance of the Senior Secured Notes was scheduled to mature on December 1, 2016.

The Senior Secured Notes are guaranteed by the Company’s U.S. domestic subsidiaries and were secured by a second priority lien, subject to first priority liens securing the Old Revolving Credit Agreement, on substantially all of the Company’s assets and those of its domestic subsidiaries. The indenture governing the Senior Secured Notes contained covenants which restricted the Company and its subsidiaries. These restrictions limited or prohibited, among other things, the Company’s ability to incur additional indebtedness; repay subordinated indebtedness prior to stated maturities; pay cash dividends on or redeem or repurchase stock or make other distributions; make investments or acquisitions; sell certain assets or merge with or into other companies; sell stock in our subsidiaries; and create liens on their assets. There are no financial covenants associated with the Senior Secured Notes.

During 2011, the Company repurchased $12.0 million of Senior Secured Notes. The Company repurchased the Senior Secured Notes at a premium of $0.3 million, which was recorded as part of interest expense in 2011. Due to the repurchase of the Senior Secured Notes, the Company also wrote-off a proportional amount of the deferred financing fees and original issue discount associated with the Senior Secured Notes totaling $0.4 million which was also recorded as part of interest expense in the Consolidated Statement of Operations and Other Comprehensive Income for 2011.

During 2012, the Company retired the remaining principal balance of the 8 1/8% Senior Secured Notes, of $198.0 million. In connection with the redemption, the Company incurred $11.4 million of pre-payment premiums and wrote-off the entire remaining balance of $4.4 million of deferred financing fees and original issue discount, which is recorded as interest expense in the Consolidated Statement of Comprehensive Income for 2012. The proceeds of the Term Loan Facility and a portion of the proceeds of the Revolving Credit Facility, along with cash on hand, were used by the Company to contribute all funds necessary to redeem all of the Company’s Senior Secured Notes.

Equipment and Working Capital Notes

The Company entered into a loan with a bank to equip its new facility in Changzhou, China during 2013. The Company is allowed to borrow up to 90% of the amount of certain outstanding letters of credit issued by the Company’s U.S. bank in favor of the lending bank in China. As of December 31, 2013, the total available to borrow was 38.5 million RMB ($6.3 million). The note is due in installments from 2014 through 2016, with interest varying between 5.04% and 6.69%. The Company has a 25.4 million RMB ($4.1 million) line of credit outstanding at December 31, 2013. The note is callable by the bank at its discretion and as such, has been included in the current portion of long-term debt in the balance sheet at December 31, 2013.

Mortgage

The Company has a mortgage with a bank on its facility in Heidelberg, Germany with an interest rate of 5.75% and is payable in monthly installments over the next three years. As of December 31, 2013 and 2012, the mortgage had a remaining principal balance of €0.5 million or $0.7 million, and €0.7 million or $1.0 million, respectively.

Capital Leases

The Company leases certain equipment under capital lease arrangements, whose obligations are included in both short-term and long-term debt. Capital lease obligations amounted to approximately $0.2 million and $0.1 million at December 31, 2013 and 2012, respectively. Assets subject to capital leases are included in property, plant and equipment with the related amortization recorded as depreciation expense.

Overdraft Agreements

Certain of our foreign subsidiaries maintain overdraft agreements with financial institutions. There were no borrowings as of December 31, 2013, 2012, or 2011 under any of the overdraft agreements.

Stockholders_Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Stockholders' Equity	'

	10. Stockholders’ Equity

	Common Stock (amounts not in thousands)

	As of December 31, 2013, there were 90,000,000 shares of common stock authorized and 26,819,795 outstanding.

	Preferred Stock

	On December 20, 2006, the Company amended and restated its certificate of incorporation authorizing 10,000,000 shares of undesignated Preferred Stock (“Preferred Stock”). The Preferred Stock may be issued from time to time in one or more classes or series, the shares of each class or series to have such designations and powers, preferences, and rights, and qualifications, limitations and restrictions as determined by the Company’s Board of Directors. There was no Preferred Stock issued or outstanding at December 31, 2013 or 2012.

	Restricted Common Stock

	The Company’s Board of Directors established the 2004 Equity Incentive Plan (as amended, the “Plan”) that provides for various forms of stock-based compensation to independent directors, officers and senior-level employees of the Company. The restricted shares issued pursuant to the Plan generally vest ratably over a period ranging from immediately to five years from the date of grant, provided, that the vesting of the restricted shares may accelerate upon the occurrence of certain liquidity events, if approved by the Board of Directors in connection with the transactions. Common stock awarded under the Plan is generally subject to restrictions on transfer, repurchase rights, and other limitations and rights as set forth in the applicable award agreements. The shares are valued based on the share price on the date of grant.

	The Plan permits the Company to grant, among other things, restricted stock, restricted stock units, and performance share awards to key employees and other persons who make significant contributions to the success of the Company. The restrictions and vesting schedule for restricted stock granted under the Plan are determined by the Personnel and Compensation Committee of the Board of Directors. Compensation expense recorded (in selling, general and administrative expense) during the years ended December 31, 2013, 2012 and 2011 was $3.2 million ($2.9 million, net of tax), $2.7 million ($1.8 million, net of tax), and $2.5 million ($1.7 million, net of tax), respectively. The Company recognizes stock-based compensation expense on a straight-line basis for the shares vesting ratably under the plan and uses the graded-vesting method of recognizing stock-based compensation expense for the performance share awards based on the probability of the specific performance metrics being achieved over the requisite service period.

	The following table sets forth the activity of the Company’s restricted stock grants to date:



	Amounts not in thousands	Shares			Weighted-
					Average Grant
					Date Fair Value
	Restricted shares unvested January 1, 2013		162,586		$	18.67
	Shares granted		128,365		$	24.58
	Shares for which restrictions lapsed		(141,316	)	$	21.55

	Restricted shares unvested December 31, 2013		149,635		$	23.02


	Total remaining unrecognized compensation cost is approximately $3.0 million as of December 31, 2013, and will be recognized over a weighted average remaining period of two years. Based on the stock price at December 31, 2013, of $34.22 per share, the intrinsic value of these awards as of December 31, 2013, was $5.1 million. The fair market value of the shares in which the restrictions have lapsed was $2.4 million, $3.2 million, and $3.3 million, during 2013, 2012, and 2011, respectively. Restricted shares granted are valued based on the fair market value of the stock on the date of grant.



	Dividends

	The Company declared quarterly dividends of $0.38 per share of common stock for the year ended December 31, 2013. On October 29, 2013, the Company declared a cash dividend of $0.10 per share for the quarter ended December 31, 2013, payable on January 3, 2014 to shareholders of record as of December 18, 2013. The dividend of $2.7 million, paid on January 3, 2014, was accrued for in the balance sheet at December 31, 2013.

	Future declarations of quarterly cash dividends are subject to approval by the Board of Directors and to the Board’s continuing determination that the declaration of dividends are in the best interest of the Company’s stockholders and are in compliance with all laws and agreements of the Company applicable to the declaration and payment of cash dividends.

Concentrations_of_Credit_Segme

Concentrations of Credit, Segment Data and Workforce	12 Months Ended
Concentrations of Credit, Segment Data and Workforce	Dec. 31, 2013
Segment Reporting [Abstract]	'
Concentrations of Credit, Segment Data and Workforce	'

	11. Concentrations of Credit, Segment Data and Workforce

	Financial instruments, which are potentially subject to counter party performance and concentrations of credit risk, consist primarily of trade accounts receivable. The Company manages these risks by conducting credit evaluations of customers prior to delivery or commencement of services. When the Company enters into a sales contract, collateral is normally not required from the customer. Payments are typically due within thirty days of billing. An allowance for potential credit losses is maintained, and losses have historically been within management’s expectations. No customer represented greater than 10% of total sales for the years ended December 31, 2013, 2012 and 2011.

	The Company is also subject to counter party performance risk of loss in the event of non-performance by counterparties to financial instruments, such as cash and investments. Cash and investments are held by well-established financial institutions and invested in AAA rated mutual funds or United States Government Securities. The Company is exposed to swap counterparty credit risk with financial institutions. The Company’s counterparty is a well-established financial institution.

	During the first quarter of 2013, the Company completed its review of its operating segments. The Company has three operating segments that are regularly reviewed by our chief operating decision maker. Each of these operating segments represents a unit that produces mechanical power transmission products. The Company aggregates all of the operating segments into one reportable segment. The three operating segments are expected to have similar long-term average gross profit margins. All of our products are sold by one global sales force and we have one global marketing function. Strategic markets and industries are determined for the entire company and then targeted by the brands. All of our operating segments have common manufacturing and production processes. Each operating segment includes a machine shop which uses similar equipment and manufacturing techniques. Each of our operating segments uses common raw materials, such as aluminum, steel and copper. The materials are purchased and procurement contracts are negotiated by one global purchasing function.

	We serve the general industrial market by selling to original equipment manufacturers (“OEM”) and distributors. Our OEM and distributor customers serve the general industrial market. Resource allocation decisions such as capital expenditure requirements and headcount requirements are made at a consolidated level and allocated to the individual operating segments.

	The following discussion of the Company’s products does not include detailed product category revenue because such information is not individually tracked by the Company’s financial reporting system and is not separately reported by the Company’s general purpose financial statements. Conducting a detailed product revenue internal assessment and audit would involve unreasonable effort and expense as revenue information by product line is not available. The Company maintains sales information by operating facility, but does not maintain any accounting sales data by product line.



		Net Sales						Property, Plant and Equipment
		Year Ended
		December 31,		December 31,		December 31,		December 31,		December 31,
		2013		2012		2011		2013		2012
	North America	$	454,115	$	469,554	$	442,931	$	87,573	$	88,051
	Europe		216,636		216,485		191,768		54,533		35,319
	Asia and the rest of the world		51,467		45,951		40,113		15,429		14,724

	Total	$	722,218	$	731,990	$	674,812	$	157,535	$	138,094


	Net sales to third parties are attributed to the geographic regions based on the country in which the shipment originates. Amounts attributed to the geographic regions for property, plant and equipment are based on the location of the entity, which holds such assets. The net assets of our foreign subsidiaries at December 31, 2013 and 2012 were $138.7 million and $117.0 million, respectively.

	Approximately 23% of the Company’s labor force (10% and 57% in the United States and Europe, respectively) is represented by collective bargaining agreements. The Company is a party to four U.S. collective bargaining agreements. The agreements will expire July 2014, October 2014, June 2014, and October 2016, respectively. The Company intends to renegotiate these contracts as they become due, though there is no assurance that this effort will be successful.

Restructuring_Asset_Impairment

Restructuring, Asset Impairment, and Transition Expenses	12 Months Ended
Restructuring, Asset Impairment, and Transition Expenses	Dec. 31, 2013
Restructuring And Related Activities [Abstract]	'
Restructuring, Asset Impairment, and Transition Expenses	'

	12. Restructuring, Asset Impairment, and Transition Expenses

	In the quarter ended December 31, 2012, the Company adopted a restructuring plan (“2012 Altra Plan”) as a result of continued sluggish demand in Europe and general global economic conditions. The actions included in the 2012 Altra Plan include reducing headcount and limiting discretionary spending to improve profitability in Europe. The Company recorded $1.1 million and $3.2 million in restructuring charges associated with the 2012 Altra Plan in 2013 and 2012. The costs were primarily severance charges due in connection with the reduction of the workforce at our European locations.

	The Company’s total restructuring expense, by major component for the years ended December 31, 2013 and 2012, were as follows:

	There was no restructuring expense for the year ended December 31, 2011.



		Year Ended			Year Ended
		December 31, 2013			December 31, 2012
		2012 Altra Plan			2012 Altra Plan
	Expenses
	Moving and relocation	$	(21	)	$	55
	Severance		1,103			2,934
	Other		29			207

	Total cash expenses		1,111			3,196
	Loss on disposal of fixed assets		—			—

	Total restructuring expenses	$	1,111		$	3,196




	The following is a reconciliation of the accrued restructuring costs between January 1, 2012 and December 31, 2013



		All Plans
	Balance at January 1, 2012	$	90
	Restructuring expense incurred		3,196
	Cash payments		(471	)
	Non-cash loss on impairment of fixed assets		—

	Balance at December 31, 2012	$	2,815

	Restructuring expense incurred		1,111
	Cash payments		(3,497	)
	Non-cash loss on impairment of fixed assets		—

	Balance at December 31, 2013	$	429


	The total restructuring reserve as of December 31, 2013 relates to severance costs to be paid to employees and is recorded in accruals and other current liabilities on the consolidated balance sheet. The Company does not expect to incur any more restructuring expenses in 2014 under the 2012 Altra Plan.

Derivative_Financial_Instrumen

Derivative Financial Instruments

12 Months Ended

Dec. 31, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

13. Derivative Financial Instruments

Interest Rate Swap

In April 2013, the Company entered into an interest rate swap agreement designed to fix the variable interest rate payable on a portion of its outstanding borrowings, currently $92.5 million, under the Credit Agreement, at 0.626% exclusive of the margin under the Former Credit Agreement. The interest rate swap agreement and its terms are also applicable to the variable interest rate borrowings under the current Credit Agreement.

The interest rate swap agreement was designed to manage exposure to interest rates on the Company’s variable rate indebtedness. The Company recognizes all derivatives on its balance sheet at fair value. The Company has designated its interest rate swap agreement, which is forward-dated, as a cash flow hedge. Changes in the fair value of the swap are recognized in other comprehensive income until the hedged items are recognized in earnings. Hedge ineffectiveness, if any, associated with the swap will be reported by the Company in interest expense. There was no ineffectiveness associated with the swap during the year ended December 31, 2013, nor was any amount excluded from ineffectiveness testing for these periods.

The fair value of the swap recognized in other non-current assets and in other comprehensive income (loss) is as follows (in thousands):

Fair Value

Effective Date

Notional Amount

Fixed Rate

Maturity

December 31,

2013

2012

30-Apr-13

92,500

0.626

November 30, 2016

213

—

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'

	14. Commitments and Contingencies

	Minimum Lease Obligations

	The Company leases certain offices, warehouses, manufacturing facilities, automobiles and equipment with various terms that range from a month to month basis to ten year terms and which, generally, include renewal provisions. Future minimum rent obligations under non-cancelable operating and capital leases are as follows:



	Year ending December 31:	Operating Leases		Capital Leases
	2014	$	7,618	$	147
	2015		6,225		28
	2016		4,847		8
	2017		2,594		6
	2018		1,892		—
	Thereafter		6,970		—

	Total lease obligations	$	30,146	$	189
	Less amounts representing interest				(8	)

	Present value of minimum capital lease obligations			$	181


	Net rent expense under operating leases for the years ended December 31, 2013, 2012, and 2011 was approximately $8.8 million, $7.8 million, $6.9 million, respectively.

	The Company also has minimum purchase contracts for inventory of €3.6 million ($4.9 million) for years 2014 and 2015.

	General Litigation

	The Company is involved in various pending legal proceedings arising out of the ordinary course of business. These proceedings primarily involve commercial claims, product liability claims, personal injury claims, and workers’ compensation claims. With respect to these proceedings, management believes that the Company will prevail, has adequate insurance coverage or has established appropriate reserves to cover potential liabilities. Any costs that management estimates may be paid related to these proceedings or claims are accrued when the liability is considered probable and the amount can be reasonably estimated. There can be no assurance, however, as to the ultimate outcome of any of these matters, and if all or substantially all of these legal proceedings were to be determined adversely to the Company, there could be a material adverse effect on the results of operations, cash flows, or financial condition of the Company. We have established loss provisions for matters in which losses are probable and can be reasonably estimated. For matters where a reserve has not been established and for which we believe a loss is reasonably possible, as well as for matters where a reserve has been recorded but for which an exposure to loss in excess of the amount accrued is reasonably possible, we believe that such losses, individually and in the aggregate, will not have a material effect on our consolidated financial statements.

	Our estimates regarding potential losses and materiality are based on our judgment and assessment of the claims utilizing currently available information. Although we will continue to reassess our reserves and estimates based on future developments, our objective assessment of the legal merits of such claims may not always be predictive of the outcome and actual results may vary from our current estimates. We will continue to consider the applicable guidance in ASC 450-20, based on the facts known at the time of our future filings, as it relates to legal contingencies, and will adjust our disclosures as may be required under the guidance.

	The Company also risks exposure to product liability claims in connection with products it has sold and those sold by businesses that the Company acquired. Although in some cases third parties have retained responsibility for product liability claims relating to products manufactured or sold prior to the acquisition of the relevant business and in other cases the persons from whom the Company has acquired a business may be required to indemnify the Company for certain product liability claims subject to certain caps or limitations on indemnification, the Company cannot assure that those third parties will in fact satisfy their obligations with respect to liabilities retained by them or their indemnification obligations. If those third parties become unable to or otherwise do not comply with their respective obligations including indemnity obligations, or if certain product liability claims for which the Company is obligated were not retained by third parties or are not subject to these indemnities, the Company could become subject to significant liabilities or other adverse consequences. Moreover, even in cases where third parties retain responsibility for product liability claims or are required to indemnify the Company, significant claims arising from products that have been acquired could have a material adverse effect on the Company’s ability to realize the benefits from an acquisition, could result in the reduction of the value of goodwill that the Company recorded in connection with an acquisition, or could otherwise have a material adverse effect on the Company’s business, financial condition, or operations.

	Environmental

	There is contamination at some of the Company’s current facilities, primarily related to historical operations at those sites, for which the Company could be liable for the investigation and remediation under certain environmental laws. The potential for contamination also exists at other of the Company current or former sites, based on historical uses of those sites. The Company currently is not undertaking any remediation or investigations and the costs or liability in connection with potential contamination conditions at these facilities cannot be predicted at this time because the potential existence of contamination has not been investigated or not enough is known about the environmental conditions or likely remedial requirements. Currently, other parties with contractual liability are addressing or have plans or obligations to address those contamination conditions that may pose a material risk to human health, safety or the environment. In addition, while the Company attempts to evaluate the risk of liability associated with these facilities at the time the Company acquired them, there may be environmental conditions currently unknown to the Company relating to prior, existing or future sites or operations or those of predecessor companies whose liabilities the Company may have assumed or acquired which could have a material adverse effect on the Company’s business.

	The Company is being indemnified, or expects to be indemnified by third parties subject to certain caps or limitations on the indemnification, for certain environmental costs and liabilities associated with certain owned or operated sites. Accordingly, based on the indemnification and the experience with similar sites of the environmental consultants who the Company has hired, the Company does not expect such costs and liabilities to have a material adverse effect on its business, operations or earnings. The Company cannot assure you, however, that those third parties will in fact satisfy their indemnification obligations. If those third parties become unable to, or otherwise do not, comply with their respective indemnity obligations, or if certain contamination or other liability for which the Company is obligated is not subject to these indemnities, the Company could become subject to significant liabilities.

	From time to time, the Company is notified that it is a potentially responsible party and may have liability in connection with off-site disposal facilities. To date, the Company has generally resolved matters involving off-site disposal facilities for a nominal sum but there can be no assurance that the Company will be able to resolve pending or future matters in a similar fashion.

	Other Matters

	The state of New York Workers’ Compensation Board (the “Compensation Board”) has demanded payment from one of the Company’s business units of certain amounts the Board alleges are owed in connection with that business unit’s past participation in a workers’ compensation insurance trust. The Company has executed Settlement Agreements with the Compensation Board to resolve the matter pursuant to which the Company has agreed to pay an aggregate amount of $0.09 in exchange for full and final releases from the Compensation Board. The Company expects to receive, but has not yet received, the final releases from the Compensation Board to formally conclude the matter. If for some reason the settlement is not completed as expected the amount claimed would currently be immaterial and would be subject to further adjustment and proceedings. As a result, absent the settlement, the total amount of potential liability could not have been reasonably estimated as of December 31, 2013.

Unaudited_Quarterly_Results_of

Unaudited Quarterly Results of Operations	12 Months Ended
Unaudited Quarterly Results of Operations	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Unaudited Quarterly Results of Operations	'

	15. Unaudited Quarterly Results of Operations:

	Year ended December 31, 2013



		Fourth			Third		Second		First
		Quarter			Quarter		Quarter		Quarter
	Net Sales	$	180,530		$	175,443	$	181,095	$	185,150
	Gross Profit		51,805			53,658		54,419		55,499
	Net income attributable to Altra Industrial Motion Corp.		7,205			10,501		10,689		11,880
	Earnings per share — Basic attributable to Altra Industrial Motion Corp.
	Net income	$	0.27		$	0.39	$	0.4	$	0.44
	Earnings per share — Diluted attributable to Altra Industrial Motion Corp.

	Net income	$	0.27		$	0.39	$	0.4	$	0.44


	Year ended December 31, 2012



		Fourth			Third		Second		First
		Quarter			Quarter		Quarter		Quarter
	Net Sales	$	177,174		$	174,488	$	187,943	$	192,385
	Gross Profit		53,862			52,011		56,002		56,673
	Net income attributable to Altra		(5,379	)		8,547		10,609		10,516
	Industrial Motion Corp.
	Earnings per share — Basic
	Net income attributable to Altra Industrial Motion Corp.	$	(0.20	)	$	0.32	$	0.4	$	0.4
	Earnings per share — Diluted

	Net income attributable to Altra Industrial Motion Corp.	$	(0.20	)	$	0.32	$	0.4	$	0.39

Subsequent_Events

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'

	16. Subsequent Events

	In February 2014, the Company’s Board of Directors approved the grant of 92,470 shares of restricted common stock or in certain cases restricted stock units, under the Company’s 2004 Equity Incentive Plan, as amended.

	The Company has declared a dividend of $0.10 per share for the quarter ended March 31, 2014, payable on April 3, 2014 to shareholders of record as of March 18, 2014.

Valuation_and_Qualifying_Accou

Valuation and Qualifying Accounts	12 Months Ended
Valuation and Qualifying Accounts	Dec. 31, 2013
Valuation And Qualifying Accounts [Abstract]	'
Valuation and Qualifying Accounts	'

	ALTRA HOLDINGS, INC.

	SCHEDULE II — VALUATION AND QUALIFYING ACCOUNTS



	Reserve for Uncollectible Accounts:	Balance at		Additions		Deductions			Balance at
		Beginning of							End of Period
		Period
	For the year ended December 31, 2011	$	1,111	$	696	$	(715	)	$	1,092
	For the year ended December 31, 2012	$	1,092	$	1,675	$	(207	)	$	2,560
	For the year ended December 31, 2013	$	2,560	$	733	$	(1,048	)	$	2,245

Description_of_Business_and_Su1

Description of Business and Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Basis of Preparation and Description of Business

Headquartered in Braintree, Massachusetts, Altra Industrial Motion Corp. (the “Company”), through its wholly-owned subsidiary Altra Power Transmissions, Inc. (“APT”), is a leading multi-national designer, producer and marketer of a wide range of electro-mechanical power transmission products. The Company brings together strong brands covering over 40 product lines with production facilities in eleven countries. Altra’s leading brands include Ameridrives Couplings, Bauer Gear Motor, Bibby Turboflex, Boston Gear, Delroyd Worm Gear, Formsprag Clutch, Huco, Industrial Clutch, Inertia Dynamics, Kilian Manufacturing, Lamiflex Couplings, Marland Clutch, Matrix, Nuttall Gear, Stieber Clutch, Svendborg Brakes, TB Wood’s, Twiflex, Warner Electric, Warner Linear, and Wichita Clutch.

In November 2013, Altra Holdings, Inc. changed its name to Altra Industrial Motion Corp., and Altra Industrial Motion, Inc., the Company’s wholly owned subsidiary, changed its name to Altra Power Transmission, Inc.

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Net Income Per Share

Basic earnings per share is based on the weighted average number of common shares outstanding. Diluted earnings per share is based on the weighted average number of common shares outstanding and all dilutive potential common equivalent shares outstanding. Common equivalent shares are included in the per share calculations when the effect of their inclusion would be dilutive.

The following is a reconciliation of basic to diluted net income per share:

Year Ended December, 31

2013

2012

2011

Net income attributable to Altra Industrial Motion Corp.

40,275

24,293

37,675

Shares used in net income per common share—basic

26,766

26,656

26,526

Incremental shares of unvested restricted common stock

100

163

Shares used in net income per common share—diluted

26,841

26,756

26,689

Earnings per share:

Basic net income attributable to Altra Industrial Motion Corp.

1.5

0.91

1.42

Diluted net income attributable to Altra Industrial Motion Corp.

1.5

0.91

1.41

The Company excluded 3,137,351 shares in 2013, 3,094,706 shares in 2012 and 784,980 shares in 2011 (amounts not in thousands) related to the Convertible Notes (See Note 9) from the above earnings per share calculation as these shares were anti-dilutive.

Fair Value of Financial Instruments

The carrying values of financial instruments, including accounts receivable, cash equivalents, accounts payable, and other accrued liabilities are carried at cost, which approximates fair value. Debt under the Company’s Credit Agreement with certain financial institutions including, a Term Loan Facility, as defined below, of $163,245,000 (the “Term Loan Facility”) and a Revolving Credit Facility, as defined below, of $200,000,000 approximate the fair values due to the variable rate nature at current market rates.

The carrying amount of the 2.75% Convertible Notes (the “Convertible Notes”) was $85.0 million at December 31, 2013 and 2012. The estimated fair value of the Convertible Notes at December 31, 2013 and 2012 was $116.5 million and $94.3 million, respectively, based on inputs other than quoted prices that are observable for the Convertible Notes (level 2).

Included in cash and cash equivalents as of December 31, 2013 and December 31, 2012 are money market fund investments of $16.6 million and $30.3 million, respectively, which are reported at fair value based on quoted market prices for such investments (level 1).

The estimated fair value of the Company’s interest rate swap agreement with certain financial institutions (“Interest Rate Swap”) at December 31, 2013 was $0.2 million, based on inputs other than quoted prices that are observable for the Interest Rate Swap (level 2). Inputs include present value of fixed and projected floating rate cash flows over the term of the swap contract. There was no Interest Rate Swap at December 31, 2012.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the financial statements. Actual results could differ from those estimates.

Non-Controlling Interest

Non-controlling Interest

On July 11, 2012, the Company acquired 85% of privately held Lamiflex do Brasil Equipamentos Industriais Ltda. (“Lamiflex”).

The Company recorded the redeemable non-controlling interest from its acquisition of an 85% ownership interest of Lamiflex at fair value at the date of acquisition. In connection with this acquisition, the Company entered into put and call option agreements with the minority shareholders for the potential purchase of the non-controlling interest at a future date at a value based on a contractually determined formula. As a result of the option agreements, the non-controlling interest is considered redeemable and is classified as temporary equity on the Company’s consolidated balance sheet. The non-controlling interest is reviewed at each subsequent reporting period and adjusted, as needed, to reflect its then redemption value.

Foreign Currency Translation

Assets and liabilities of subsidiaries operating outside of the United States with a functional currency other than the U.S. Dollar are translated into U.S. Dollars using exchange rates at the end of the respective period. Revenues and expenses are translated at average exchange rates effective during the respective period.

Foreign currency translation adjustments are included in accumulated other comprehensive income as a separate component of stockholders’ equity. Net foreign currency transaction gains and losses are included in the results of operations in the period incurred and included in other non-operating expense (income), net in the accompanying statements of comprehensive income.

Trade Receivables

An allowance for doubtful accounts is recorded for estimated collection losses that will be incurred in the collection of receivables. Estimated losses are based on historical collection experience, as well as a review by management of the status of all receivables. Collection losses have been within the Company’s expectations.

Inventories

Inventories are stated at the lower of cost or market using the first-in, first-out (“FIFO”) method for all entities excluding one of the Company’s subsidiaries, TB Wood’s. TB Wood’s inventory is stated at the lower of cost or market, principally using the last-in, first-out (“LIFO”) method. Inventory stated using the LIFO method approximates 7.5% and 10% of total inventory at December 31, 2013 and 2012, respectively.

The cost of inventories acquired by the Company in its acquisitions reflect their fair values at the date of acquisition as determined by the Company based on the replacement cost of raw materials, the sales price of the finished goods less an appropriate amount representing the expected profitability from selling efforts, and for work-in-process the sales price of the finished goods less an appropriate amount representing the expected profitability from selling efforts and costs to complete.

The Company periodically reviews its quantities of inventories on hand and compares these amounts to the expected usage of each particular product or product line. The Company records a charge to cost of sales for any amounts required to reduce the carrying value of inventories to its estimated net realizable value.

Property, Plant and Equipment

Property, plant and equipment are stated at cost, net of accumulated depreciation.

Depreciation of property, plant and equipment, including capital leases is provided using the straight-line method over the estimated useful life of the asset, as follows:

Buildings and improvements

15 to 45 years

Machinery and equipment

2 to 15 years

Capital lease

Life of lease

Leasehold improvements are depreciated on a straight-line basis over the estimated life of the asset or the life of the lease, if shorter.

Improvements and replacements are capitalized to the extent that they increase the useful economic life or increase the expected economic benefit of the underlying asset. Repairs and maintenance expenditures are charged to expense as incurred.

Intangible Assets

Intangibles represent product technology, patents, tradenames, trademarks and customer relationships. Product technology, patents and customer relationships are amortized on a straight-line basis over 8 to 17 years, which approximates the period of economic benefit. The tradenames and trademarks are considered indefinite-lived assets and are not being amortized. Intangibles are stated at fair value on the date of acquisition. At December 31, 2013 and 2012, intangibles are stated net of accumulated amortization incurred since the date of acquisition and any impairment charges.

Goodwill

Goodwill represents the excess of the purchase price paid by the Company over the fair value of the net assets acquired in each of the Company’s acquisitions.

Impairment of Goodwill and Indefinite-Lived Intangible Assets

The Company conducts an annual impairment review of goodwill and indefinite-lived intangible assets in December of each year, unless events occur which trigger the need for an interim impairment review.

In connection with the Company’s annual impairment review, goodwill is assessed for impairment by comparing the fair value of the reporting unit to the carrying value using a two-step approach. In the first step, the Company estimates future cash flows based upon historical results and current market projections, discounted at a market comparable rate. If the carrying amount of the reporting unit exceeds the estimated fair value, impairment may be present, the Company would then be required to perform a second step in its impairment analysis. In the second step, the Company would evaluate impairment losses based upon the fair value of the underlying assets and liabilities of the reporting unit, including any unrecognized intangible assets, and estimate the implied fair value of the goodwill. An impairment loss is recognized to the extent that a reporting unit’s recorded value of the goodwill asset exceeded its calculated fair value. In addition, to the extent the implied fair value of any indefinite-lived intangible asset is less than the asset’s carrying value, an impairment loss is recognized on those assets. The Company did not identify any impairment of goodwill in 2013, 2012 or 2011.

For our indefinite-lived intangible assets, mainly trademarks, we estimated the fair value first by estimating the total revenue attributable to the trademarks for each of the reporting units. Second, we estimated an appropriate royalty rate using the return on assets method by estimating the required financial return on our assets, excluding trademarks, less the overall return generated by our total asset base. The return as a percentage of revenue provides an indication of our royalty rate (between 1.0% and 1.5%). We compared the estimated fair value of our trademarks with the carrying value of the trademarks and did not identify any impairment.

Preparation of forecasts of revenue and profitability growth for use in the long-range plan and the discount rate require significant use of judgment. Changes to the discount rate and the forecasted profitability could affect the estimated fair value of one or more of the Company’s reporting units and could result in a goodwill impairment charge in a future period.

Impairment of Long-Lived Assets Other Than Goodwill and Indefinite-Lived Intangible Assets

Long-lived assets, including definite-lived intangible assets, are reviewed for impairment when events or circumstances indicate that the carrying amount of a long-lived asset may not be recovered. Long-lived assets are considered to be impaired if the carrying amount of the asset exceeds the undiscounted future cash flows expected to be generated by the asset over its remaining useful life. If an asset is considered to be impaired, the impairment is measured by the amount by which the carrying amount of the asset exceeds its fair value, and is charged to results of operations at that time.

The Company did not identify any impairment of long-lived assets in 2013 or 2012. In relation to the sale of the Stratford facility in 2011, the Company identified and recorded an impairment with respect to the facility in the amount of $0.1 million based on their fair market value (Note 4).

Determining fair values based on discounted cash flows requires management to make significant estimates and assumptions, including forecasting of revenue and profitability growth for use in the long-range plan and estimating appropriate discount rates. Changes to the discount rate and the forecasted profitability could affect the estimated fair value of one or more of the Company’s indefinite-lived intangible assets and could result in an impairment charge in a future period.

Debt Issuance Costs

Costs directly related to the issuance of debt are capitalized, included in other non-current assets and amortized using the effective interest method over the term of the related debt obligation. The net carrying value of debt issuance costs was approximately $4.1 million and $4.3 million at December 31, 2013 and 2012, respectively.

Revenue Recognition

Product revenues are recognized, net of sales tax collected, at the time title and risk of loss pass to the customer, which generally occurs upon shipment to the customer. Product return reserves are accrued at the time of sale based on the historical relationship between shipments and returns, and are recorded as a reduction of net sales.

Certain large distribution customers receive annual volume discounts, which are estimated at the time the sale is recorded based on the estimated annual sales.

Shipping and Handling Costs

Shipping and handling costs associated with sales are classified as a component of cost of sales.

Warranty Costs

Estimated expenses related to product warranties are accrued at the time products are sold to customers. Estimates are established using historical information as to the nature, frequency, and average costs of warranty claims. See Note 6 to the consolidated financial statements.

Self-Insurance

Certain exposures are self-insured up to pre-determined amounts, above which third-party insurance applies, for medical claims, workers’ compensation, vehicle insurance, product liability costs and general liability exposure. The accompanying balance sheets include reserves for the estimated costs associated with these self-insured risks, based on historic experience factors and management’s estimates for known and anticipated claims. A portion of medical insurance costs are offset by charging employees a premium equivalent to group insurance rates.

Research and Development

Research and development costs are expensed as incurred.

Advertising

Advertising costs are charged to selling, general and administrative expenses as incurred and amounted to approximately $2.5 million, $2.1 million and $1.5 million, for the years ended December 31, 2013, 2012, and 2011, respectively.

Stock-Based Compensation

The Company established the 2004 Equity Incentive Plan, as amended, that provides for various forms of stock-based compensation to officers, directors, key employees and others who make significant contributions to the success of the Company. The Company recognizes stock based compensation expense on a straight line basis for shares vesting ratably under the plan and uses the graded-vesting method of recognizing stock-based compensation expense for performance share awards based on the probability of the specific performance metrics being achieved over the requisite service period.

Income Taxes

The Company records income taxes using the asset and liability method. Deferred income tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective income tax bases, and operating loss and tax credit carryforwards. The Company evaluates the realizability of its net deferred tax assets and assesses the need for a valuation allowance on a quarterly basis. The future benefit to be derived from its deferred tax assets is dependent upon the Company’s ability to generate sufficient future taxable income to realize the assets. The Company records a valuation allowance to reduce its net deferred tax assets to the amount that may be more likely than not to be realized.

To the extent the Company establishes a valuation allowance on net deferred tax assets generated from operations, an expense will be recorded within the provision for income taxes. In periods subsequent to establishing a valuation allowance on net deferred assets from operations, if the Company were to determine that it would be able to realize its net deferred tax assets in excess of their net recorded amount, an adjustment to the valuation allowance would be recorded as a reduction to income tax expense in the period such determination was made.

We assess our income tax positions and record tax benefits for all years subject to examination, based upon our evaluation of the facts, circumstances and information available at the reporting date. For those tax positions for which it is more likely than not that a tax benefit will be sustained, we record the amount that has a greater than 50% likelihood of being realized upon settlement with the taxing authority that has full knowledge of all relevant information. Interest and penalties are accrued, where applicable. If we do not believe that it is more likely than not that a tax benefit will be sustained, no tax benefit is recognized.

Contingencies Policy

We will continue to consider the applicable guidance in ASC 450-20, based on the facts known at the time of our future filings, as it relates to legal contingencies, and will adjust our disclosures as may be required under the guidance.

Changes in Accumulated Other Comprehensive Loss by Component

The following is a reconciliation of changes in Accumulated Other Comprehensive Loss by Component for the periods presented:

Cash Flow

Defined

Cumulative

Total

Hedges

Benefit

Foreign

Pension Plans

Currency

Translation

Accumulated Other Comprehensive Loss by Component, January 1, 2012

—

(2,485

)

(22,591

)

(25,076

)

Net current-period Other Comprehensive Income Loss

—

(2,122

)

3,795

1,673

Accumulated Other Comprehensive Loss by component, January 1, 2013

—

(4,607

)

(18,796

)

(23,403

)

Net current-period Other Comprehensive Income

135

1,474

3,398

5,007

Accumulated Other Comprehensive Income (Loss) by component, December 31, 2013

135

(3,133

)

(15,398

)

(18,396

)

Description_of_Business_and_Su2

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Reconciliation of Basic to Diluted Net Income Per Share	'

	The following is a reconciliation of basic to diluted net income per share:



		Year Ended December, 31
		2013		2012			2011
	Net income attributable to Altra Industrial Motion Corp.	$	40,275	$	24,293		$	37,675
	Shares used in net income per common share — basic		26,766		26,656			26,526
	Incremental shares of unvested restricted common stock		75		100			163

	Shares used in net income per common share — diluted		26,841		26,756			26,689
	Earnings per share:
	Basic net income attributable to Altra Industrial Motion Corp.	$	1.5	$	0.91		$	1.42
	Diluted net income attributable to Altra Industrial Motion Corp.	$	1.5	$	0.91		$	1.41
Depreciation of Property, Plant and Equipment, Including Capital Leases is Provided Using Straight-Line Method Over Estimated Useful Life of Asset	'
	Depreciation of property, plant and equipment, including capital leases is provided using the straight-line method over the estimated useful life of the asset, as follows:


	Buildings and improvements		15 to 45 years
	Machinery and equipment		2 to 15 years
	Capital lease		Life of lease
Changes in Accumulated Other Comprehensive Loss by Component	'

	The following is a reconciliation of changes in Accumulated Other Comprehensive Loss by Component for the periods presented:



		Cash Flow		Defined			Cumulative			Total
		Hedges		Benefit			Foreign
				Pension Plans			Currency
							Translation
	Accumulated Other Comprehensive Loss by Component, January 1, 2012	$	—	$	(2,485	)	$	(22,591	)	$	(25,076	)
	Net current-period Other Comprehensive Income Loss		—		(2,122	)		3,795			1,673

	Accumulated Other Comprehensive Loss by component, January 1, 2013	$	—	$	(4,607	)	$	(18,796	)	$	(23,403	)

	Net current-period Other Comprehensive Income		135		1,474			3,398			5,007

	Accumulated Other Comprehensive Income (Loss) by component, December 31, 2013	$	135	$	(3,133	)	$	(15,398	)	$	(18,396	)

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
Acquisitions (Tables)	Dec. 31, 2013
Proforma Amount on Acquisition Occurred	'

	These pro forma amounts do not purport to be indicative of the results that would have actually been obtained if the acquisition occurred at the beginning of the period or that may be obtained in the future.



		2013		2012		2011
	Total revenues	$	803,467	$	818,956	$	732,837
	Net income attributable to Altra Industrial Motion Corp.	$	37,750	$	22,373	$	41,718
	Basic earnings per share:
	Net income attributable to Altra Industrial Motion Corp.	$	1.41	$	0.84	$	1.57
	Diluted earnings per share:
	Net income attributable to Altra Industrial Motion Corp.	$	1.41	$	0.84	$	1.56
Svendborg [Member]	'
Preliminary Purchase Price Allocation as of Acquisition Date	'

	Purchase price, excluding acquisition costs of approximately $2.5 million	$	102,096
	Cash and cash equivalents		7,483
	Trade receivables, net of amounts pledged		21,575
	Inventories		25,452
	Prepaid and other		5,511
	Property, plant and equipment		12,216
	Other assets		1,133
	Intangible assets		48,893

	Total assets acquired	$	122,263
	Accounts payable		4,833
	Accrued expenses and other current liabilities		9,620
	Taxes payable		10,254
	Deferred tax liability		11,483

	Total liabilities assumed	$	36,190
	Net assets acquired		86,073

	Excess of purchase price over fair value of net assets acquired	$	16,023

Amounts Recorded as Intangible Assets	'
	The amounts recorded as intangible assets consist of the following:


	Customer relationships, subject to amortization	$	40,050
	Trade names and trademarks, not subject to amortization		8,500
	Patents		343

	Total intangible assets	$	48,893

Lamiflex [Member]	'
Preliminary Purchase Price Allocation as of Acquisition Date	'
	The purchase price allocation as of the acquisition date is as follows:


	Total Assumed purchase price, excluding acquisition costs of approximately $0.4 million	$	8,820
	Less: Redeemable noncontrolling interest		1,327

	Total purchase price paid at closing		7,493
	Cash and cash equivalents		68
	Trade receivables, net of amounts pledged		606
	Inventories		726
	Prepaid and other		48
	Property, plant and equipment		3,027
	Other assets		108
	Intangible assets		4,912

	Total assets acquired	$	9,495
	Accounts payable		550
	Accrued expenses and other current liabilities		867
	Deferred tax liability		1,934
	Other liabilities, including long-term debt		976

	Total liabilities assumed	$	4,327
	Net assets acquired		5,168

	Excess of purchase price over fair value of net assets acquired		3,652

Amounts Recorded as Intangible Assets	'
	The estimated amounts recorded as intangible assets in connection with the Lamiflex Acquisition consist of the following:


	Customer relationships, subject to amortization	$	4,552
	Trade names and trademarks, not subject to amortization		360

	Total intangible assets	$	4,912

Inventories_Tables

Inventories (Tables)	12 Months Ended
Inventories (Tables)	Dec. 31, 2013
Inventory Disclosure [Abstract]	'
Summary of Inventories	'
	Inventories at December 31, 2013 and 2012 consisted of the following:


		December 31,		December 31,
		2013		2012
	Raw materials	$	56,824	$	39,902
	Work in process		18,432		21,199
	Finished goods		68,409		62,675

	Inventories, net	$	143,665	$	123,776

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	12 Months Ended
Property, Plant and Equipment (Tables)	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Schedule of Property, Plant and Equipment	'
	Property, plant and equipment at December 31, 2013 and 2012, consisted of the following:


		2013			2012
	Land	$	20,803		$	13,565
	Buildings and improvements		53,078			38,942
	Machinery and equipment		207,193			190,809

			281,074			243,316
	Less -Accumulated depreciation		(123,539	)		(105,222	)

		$	157,535		$	138,094

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	12 Months Ended
Goodwill and Intangible Assets (Tables)	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'
Changes in Goodwill	'
	Changes in goodwill during the year ended December 31, 2013 and 2012 were as follows:


		2013			2012
	Gross goodwill balance as of January 1	$	120,035		$	115,609
	Adjustments related to the acquisition of Svendborg in 2013 and Lamiflex in 2012		16,023			3,652
	Impact of changes in foreign currency and other		91			774

	Gross goodwill balance as of December 31		136,149			120,035

	Accumulated impairment, January 1		(31,810	)		(31,810	)
	Impairment charge during period		—			—
	Accumulated impairment, December 31		(31,810	)		(31,810	)

	Net goodwill balance December 31	$	104,339		$	88,225

Intangibles and Related Accumulated Amortization	'

	Intangibles and related accumulated amortization consisted of the following:



		December 31, 2013						December 31, 2012
		Cost			Accumulated			Cost			Accumulated
		Cost			Amortization			Cost			Amortization
	Intangible Assets
	Intangible assets not subject to amortization:
	Tradenames and trademarks	$	42,985		$	—		$	34,485		$	—
	Intangible assets subject to amortization:
	Customer relationships		118,914			42,645			78,864			36,202
	Product technology and patents		6,062			5,719			5,719			5,657
	Impact of changes in foreign currency		(829	)		—			(1,111	)		—

	Total intangible assets	$	167,132		$	48,364		$	117,957		$	41,859

Warranty_Costs_Tables

Warranty Costs (Tables)	12 Months Ended
Warranty Costs (Tables)	Dec. 31, 2013
Guarantees [Abstract]	'
Changes in Carrying Amount of Accrued Product Warranty Costs	'
	Changes in the carrying amount of accrued product warranty costs for each of the years ended December 31, 2013, 2012, and 2011 are as follows:


		December 31,			December 31,			December 31,
		2013			2012			2011
	Balance at beginning of period	$	5,625		$	4,898		$	3,583
	Accrued current period warranty costs		2,573			2,386			2,374
	Acquired warranty reserves		3,420			—			1,720
	Payments and adjustments		(2,879	)		(1,659	)		(2,779	)

	Balance at end of period	$	8,739		$	5,625		$	4,898

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Before Income Taxes by Domestic and Foreign Locations	'

	Income before income taxes by domestic and foreign locations consists of the following:



		December 31,			December 31,			December 31,
		2013			2012			2011
	Domestic	$	37,640		$	18,083		$	34,034
	Foreign		21,696			16,276			14,397

	Total	$	59,336		$	34,359		$	48,431
Components of Provision (Benefit) for Income Taxes	'

	The components of the provision (benefit) for income taxes consist of the following:



		December 31,			December 31,			December 31,
		2013			2012			2011
	Current:
	Federal	$	8,917		$	8,370		$	4,506
	State		698			(3,597	)		(3,686	)
	Non-US		6,072			6,006			5,057

		$	15,687		$	10,779		$	5,877

	Deferred:
	Federal	$	3,533		$	(915	)	$	7,949
	State		378			1,756			(861	)
	Non-US		(447	)		(1,466	)		(2,209	)

			3,464			(625	)		4,879

	Provision (benefit) for income taxes	$	19,151		$	10,154		$	10,756

Reconciliation from Tax at U.S. Federal Statutory Rate to Company's Provision (Benefit) for Income Taxes	'

	A reconciliation from tax at the U.S. federal statutory rate to the Company’s provision (benefit) for income taxes is as follows:



		December 31,			December 31,			December 31,
		2013			2012			2011
	Tax at US federal income tax rate	$	20,767		$	12,026		$	16,957
	State taxes, net of federal income tax effect		905			67			1,050
	Change in tax rate		(354	)		(267	)		(236	)
	Foreign taxes		(224	)		781			709
	Adjustments to accrued income tax liabilities and uncertain tax positions		(52	)		(1,289	)		(3,413	)
	Valuation allowance		120			506			(1,644	)
	Intercompany interest		(986	)		(1,676	)		(1,178	)
	Tax credits and incentives		(816	)		(291	)		(1,243	)
	Domestic Manufacturing Deduction		(839	)		(566	)		(544	)
	Other		630			863			298

	Provision (benefit) for income taxes	$	19,151		$	10,154		$	10,756

Reconciliation of Gross Amount of Unrecognized Tax Benefits Excluding Accrued Interest and Penalties	'

	A reconciliation of the gross amount of unrecognized tax benefits excluding accrued interest and penalties is as follows:



		December 31,			December 31,			December 31,
		2013			2012			2011
	Balance at beginning of period	$	747		$	3,523		$	6,338
	Increases related to prior year tax positions		—			—			—
	Decreases related to prior year tax positions		(33	)		—			(2,289	)
	Increases related to current year tax positions		—			—			—
	Settlements		—			(2,689	)		—
	Lapse of statute of limitations		(87	)		(87	)		(526	)

	Balance at end of period	$	627		$	747		$	3,523

Significant Components of Deferred Tax Assets and Liabilities	'

	Significant components of the deferred tax assets and liabilities as of December 31, 2013 and 2012 are as follows:



		2013			2012
	Deferred tax assets:
	Post-retirement obligations	$	1,565		$	3,157
	Tax credits		2,165			2,040
	Expenses not currently deductible		11,788			11,598
	Net operating loss carryover		6,376			6,435
	Other		546			790

	Total deferred tax assets		22,440			24,020
	Valuation allowance for deferred tax assets		(5,577	)		(5,426	)

	Net deferred tax assets		16,863			18,594
	Deferred tax liabilities:
	Property, plant and equipment		20,065			19,892
	Intangible assets		25,090			14,969
	Basis difference - convertible debt		11,064			10,212
	Goodwill		3,813			2,308

	Total deferred liabilities		60,032			47,381

	Net deferred tax liabilities	$	43,169		$	28,787

Pension_and_Other_Employee_Ben1

Pension and Other Employee Benefits (Tables)	12 Months Ended
Pension and Other Employee Benefits (Tables)	Dec. 31, 2013
Compensation And Retirement Disclosure [Abstract]	'
Reconciliation of Benefit Obligation, Fair Value of Plan Assets and Funded Status of Respective Defined Benefit (Pension) and Postretirement Benefit Plans	'

	The following tables represent the reconciliation of the benefit obligation, fair value of plan assets and funded status of the respective defined benefit (pension) plans as of December 31, 2013 and 2012:



		Pension Benefits
		Year Ended			Year Ended
		December 31,			December 31,
		2013			2012
	Change in benefit obligation:
	Obligation at beginning of period	$	34,629		$	29,415
	Assumed Bauer pension liability		—			—
	Service cost		248			179
	Interest cost		1,250			1,381
	Curtailments, settlements and special termination benefits		—			—
	Actuarial (gains) losses		(2,969	)		4,574
	Foreign exchange effect		343			153
	Benefits paid		(1,286	)		(1,073	)

	Obligation at end of period	$	32,215		$	34,629

	Change in plan assets:
	Fair value of plan assets, beginning of period	$	20,100		$	16,519
	Assumed Bauer plan assets		—			—
	Actual return on plan assets		182			2,035
	Employer contributions		5,194			2,619
	Benefits paid		(1,286	)		(1,073	)

	Fair value of plan assets, end of period	$	24,190		$	20,100

	Funded status	$	(8,025	)	$	(14,529	)

	Amounts Recognized in the balance sheet consist of:
	Non current assets	$	—		$	—
	Current liabilities		—			—
	Non-current liabilities		(8,025	)		(14,529	)

	Total	$	(8,025	)	$	(14,529	)

Discount Rate Used in Computation of Respective Benefit Obligations	'

	The discount rate used in the computation of the respective benefit obligations at December 31, 2013 and 2012, presented above are as follows:



		2013			2012
	Pension benefits		4.6	%		3.75	%
Components of Net Periodic Benefit Cost	'

	The following table represents the components of the net periodic benefit cost associated with the respective plans:



		Pension Benefits
		Year Ended			Year Ended				Year Ended
		December 31,			December 31,				December 31,
		2013			2012				2011
	Service cost	$	248		$	179			$	167
	Interest cost		1,250			1,381				1,389
	Recognized net actuarial loss		—			—				—
	Expected return on plan assets		(1,080	)		(1,083	)			(1,050	)
	Settlement/Curtailment/ Special Termination Benefit		—			—				—
	Amortization		175			105				39

	Net periodic benefit (income) cost	$	593		$	582			$	545

Economic Assumptions Used in Computation of Respective Net Periodic Benefit Cost	'

	The key economic assumptions used in the computation of the respective net periodic benefit cost for the periods presented above are as follows:



		Pension Benefits
		Year Ended			Year Ended				Year Ended
		December 31,			December 31,				December 31,
		2013			2012				2011
	Discount rate		3.75	%		4.75	%			5.5	%
	Expected return on plan assets		5.25	%		6.25	%			7.75	%
	Compensation rate increase		N/A			N/A				N/A
Schedule of Fair Value of Pension Plan Assets	'

	The fair value of the Company’s pension plan assets at December 31, 2013 and 2012 by asset category is as follows:



			2013			2012
	Asset Category
	Equity (Level 1)
	U.S. companies	$	—		$	4,522
	International companies		—			297

	Total equity		—			4,819
	Fixed income (Level 1)
	U.S. government		2,787			820
	Corporate bonds
	Investment grade		17,091			8,738
	High yield		3,634			3,151
	Other credit		—			1,632

	Total fixed income		23,512			14,341
	Other (Level 2)		338			328
	Cash and cash equivalents (Level 1)		340			612

	Total assets at fair value	$	24,190		$	20,100

Schedule of Asset Allocations for Funded Retirement Plan	'

	The asset allocations for the Company’s funded retirement plan at December 31, 2013 and 2012, respectively, and the target allocation for 2013, by asset category, are as follows:



		Allocation Percentage of
		Plan Assets at Year-End
		2013			2013		2012
		Actual			Target		Actual
	Asset Category
	Global Developed Equity		0	%	0%			5	%
	Investment Grade Bonds		84	%	20% - 100%			48	%
	High Yield Bonds		15	%	0% - 25%			16	%
	Cash		1	%	0% - 5%			3	%
	Emerging Market Debt		0	%	0%			3	%
	Dynamic Asset Allocation/Alternatives		0	%	0%			25	%
Summary of Amounts of Expected Benefit Payments	'

	The following table provides the amounts of expected benefit payments, which are made from the plans’ assets and includes the participants’ share of the costs, which is funded by participant contributions. The amounts in the table are actuarially determined and reflect the Company’s best estimate given its current knowledge; actual amounts could be materially different.



		Pension
		Benefits
	Expected benefit payments (from plan assets)
	2014		1,153
	2015		1,309
	2016		1,370
	2017		1,399
	2018		1,464
	Thereafter		7,895

LongTerm_Debt_Tables

Long-Term Debt (Tables)	12 Months Ended
Long-Term Debt (Tables)	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Outstanding Debt Obligations	'
		December 31,				December 31,
			2013				2012
	Debt:
	Revolving Credit Facility		$	41,198			$	79,304
	Convertible Notes			85,000				85,000
	Term Loan Facility			163,245				100,000
	Equipment Loan			4,155				1,100
	Mortgages			659				963
	Capital leases			178				99
	Other			—				435
	Total debt			294,435				266,901
	Less: debt discount, net of accretion			(16,163	)			(19,306	)

	Total debt, net of unaccreted discount		$	278,272			$	247,595

	Less current portion of long-term debt			16,924				9,135

	Total long-term debt		$	261,348			$	238,460

Carrying Amount of Debt	'
	The carrying amount of the principal amount of the liability component, the unamortized discount, and the net carrying amount are as follows as of December 31, 2013:


			December 31,
			2013
	Principal amount of debt		$	85,000
	Unamortized discount			16,163

	Carrying value of debt		$	68,837

Interest Expense Associated with Convertible Notes	'
	Interest expense associated with the Convertible Notes consisted of the following for the year ended December 31, 2013:


			December 31,
			2012
	Contractual coupon rate of interest		$	2,338
	Accretion of Convertible Notes discount and amortization of deferred financing costs			3,494

	Interest expense for the Convertible Notes		$	5,832

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
Stockholders' Equity (Tables)	Dec. 31, 2013
Equity [Abstract]	'
Schedule of Activity of Company's Restricted Stock Grants	'

	The following table sets forth the activity of the Company’s restricted stock grants to date:



	Amounts not in thousands	Shares			Weighted-
					Average Grant
					Date Fair Value
	Restricted shares unvested January 1, 2013		162,586		$	18.67
	Shares granted		128,365		$	24.58
	Shares for which restrictions lapsed		(141,316	)	$	21.55

	Restricted shares unvested December 31, 2013		149,635		$	23.02

Concentrations_of_Credit_Segme1

Concentrations of Credit, Segment Data and Workforce (Tables)	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Net Sales to Third Parties and Property, Plant and Equipment by Geographic Region	'

	Net sales to third parties and property, plant and equipment by geographic region are as follows:


		Net Sales				Property, Plant and Equipment
		Year Ended
		December 31,		December 31,		December 31,		December 31,		December 31,
		2013		2012		2011		2013		2012
	North America	$	454,115	$	469,554	$	442,931	$	87,573	$	88,051
	Europe		216,636		216,485		191,768		54,533		35,319
	Asia and the rest of the world		51,467		45,951		40,113		15,429		14,724

	Total	$	722,218	$	731,990	$	674,812	$	157,535	$	138,094

Restructuring_Asset_Impairment1

Restructuring, Asset Impairment, and Transition Expenses (Tables)	12 Months Ended
	Dec. 31, 2013
Restructuring And Related Activities [Abstract]	'
Summary of Total Restructuring Expense	'

	The Company’s total restructuring expense, by major component for the years ended December 31, 2013 and 2012, were as follows:



		Year Ended			Year Ended
		December 31, 2013			December 31, 2012
		2012 Altra Plan			2012 Altra Plan
	Expenses
	Moving and relocation	$	(21	)	$	55
	Severance		1,103			2,934
	Other		29			207

	Total cash expenses		1,111			3,196
	Loss on disposal of fixed assets		—			—

	Total restructuring expenses	$	1,111		$	3,196

Reconciliation of Accrued Restructuring Costs	'

	The following is a reconciliation of the accrued restructuring costs between January 1, 2012 and December 31, 2013



		All Plans
	Balance at January 1, 2012	$	90
	Restructuring expense incurred		3,196
	Cash payments		(471	)
	Non-cash loss on impairment of fixed assets		—

	Balance at December 31, 2012	$	2,815

	Restructuring expense incurred		1,111
	Cash payments		(3,497	)
	Non-cash loss on impairment of fixed assets		—

	Balance at December 31, 2013	$	429

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2013

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Summary of Swap Recognized in Other Non-Current Assets and in Other Comprehensive Income (Loss)

The fair value of the swap recognized in other non-current assets and in other comprehensive income (loss) is as follows (in thousands):

Fair Value

Effective Date

Notional Amount

Fixed Rate

Maturity

December 31,

2013

2012

30-Apr-13

92,500

0.626

November 30, 2016

213

—

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
Commitments and Contingencies (Tables)	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Future Minimum Rent Obligations under Non-Cancelable Operating and Capital Leases	'

	Future minimum rent obligations under non-cancelable operating and capital leases are as follows:



	Year ending December 31:	Operating Leases		Capital Leases
	2014	$	7,618	$	147
	2015		6,225		28
	2016		4,847		8
	2017		2,594		6
	2018		1,892		—
	Thereafter		6,970		—

	Total lease obligations	$	30,146	$	189
	Less amounts representing interest				(8	)

	Present value of minimum capital lease obligations			$	181

Unaudited_Quarterly_Results_of1

Unaudited Quarterly Results of Operations (Tables)	12 Months Ended
Unaudited Quarterly Results of Operations (Tables)	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Schedule of Quarterly Results of Operations	'

	Year ended December 31, 2013



		Fourth			Third		Second		First
		Quarter			Quarter		Quarter		Quarter
	Net Sales	$	180,530		$	175,443	$	181,095	$	185,150
	Gross Profit		51,805			53,658		54,419		55,499
	Net income attributable to Altra Industrial Motion Corp.		7,205			10,501		10,689		11,880
	Earnings per share — Basic attributable to Altra Industrial Motion Corp.
	Net income	$	0.27		$	0.39	$	0.4	$	0.44
	Earnings per share — Diluted attributable to Altra Industrial Motion Corp.

	Net income	$	0.27		$	0.39	$	0.4	$	0.44


	Year ended December 31, 2012



		Fourth			Third		Second		First
		Quarter			Quarter		Quarter		Quarter
	Net Sales	$	177,174		$	174,488	$	187,943	$	192,385
	Gross Profit		53,862			52,011		56,002		56,673
	Net income attributable to Altra		(5,379	)		8,547		10,609		10,516
	Industrial Motion Corp.
	Earnings per share — Basic
	Net income attributable to Altra Industrial Motion Corp.	$	(0.20	)	$	0.32	$	0.4	$	0.4
	Earnings per share — Diluted

	Net income attributable to Altra Industrial Motion Corp.	$	(0.20	)	$	0.32	$	0.4	$	0.39

Description_of_Business_and_Su3

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jul. 11, 2012
	Reporting_Unit	Dec. 31, 2012	Dec. 31, 2011	Jul. 11, 2012
Organization And Nature Of Business [Line Items]	'	'	'	'
Anti-dilutive shares	3,137,351	3,094,706	784,980	'
Percentage of ownership acquired	'	'	'	85.00%
Number of entity subsidiaries excluded	'one	'	'	'
Percentage of inventory LIFO	7.50%	10.00%	'	'
Impairment of goodwill	$0	$0	$0	'
Company's reporting units	1	'	'	'
Impairment of long-lived assets	0	0	100,000	'
Net carrying value of debt issuance cost	4,100,000	4,300,000	'	'
Advertising costs	2,500,000	2,100,000	1,500,000	'
Tax benefit sustainable	'greater than 50%	'	'	'
Convertible Notes [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Estimated fair value of financial instruments	116,500,000	94,300,000	'	'
Carrying amount of financial instruments	85,000,000	85,000,000	'	'
Interest on notes	2.75%	2.75%	'	'
Minimum [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Amortization straight-line basis	'8 years	'	'	'
Royalty rate indication based on return as a percentage of revenue	1.00%	'	'	'
Maximum [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Amortization straight-line basis	'17 years	'	'	'
Royalty rate indication based on return as a percentage of revenue	1.50%	'	'	'
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Estimated fair value of interest rate swap	200,000	0	'	'
Money Market Funds [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Cash and cash equivalents	16,600,000	30,300,000	'	'
Brand [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Number of product lines	40	'	'	'
Production facilities in number of countries	11	'	'	'
Term Loan Facility [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Estimated fair value of financial instruments	163,245,000	'	'	'
Revolving Credit Facility [Member]	'	'	'	'
Organization And Nature Of Business [Line Items]	'	'	'	'
Estimated fair value of financial instruments	$200,000,000	'	'	'

Description_of_Business_and_Su4

Description of Business and Summary of Significant Accounting Policies - Reconciliation of Basic to Diluted Net Income Per Share (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 31, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Net income attributable to Altra Industrial Motion Corp.	$7,205	$10,501	$10,689	$11,880	($5,379)	$8,547	$10,609	$10,516	$40,275	$24,293	$37,675
Shares used in net income per common share - basic	'	'	'	'	'	'	'	'	26,766	26,656	26,526
Incremental shares of unvested restricted common stock	'	'	'	'	'	'	'	'	75	100	163
Shares used in net income per common share - diluted	'	'	'	'	'	'	'	'	26,841	26,756	26,689
Earnings per share:	'	'	'	'	'	'	'	'	'	'	'
Basic net income attributable to Altra Industrial Motion Corp.	$0.27	$0.39	$0.40	$0.44	($0.20)	$0.32	$0.40	$0.40	$1.50	$0.91	$1.42
Diluted net income attributable to Altra Industrial Motion Corp.	$0.27	$0.39	$0.40	$0.44	($0.20)	$0.32	$0.40	$0.39	$1.50	$0.91	$1.41

Description_of_Business_and_Su5

Description of Business and Summary of Significant Accounting Policies - Depreciation of Property, Plant and Equipment, Including Capital Leases is Provided Using Straight-Line Method Over Estimated Useful Life of Asset (Detail)	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Line Items]	'
Capital lease	'Life of lease
Minimum [Member] \| Buildings and Improvements [Member]	'
Property, Plant and Equipment [Line Items]	'
Buildings and improvements/Machinery and equipment	'15 years
Minimum [Member] \| Machinery and Equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Buildings and improvements/Machinery and equipment	'2 years
Maximum [Member] \| Buildings and Improvements [Member]	'
Property, Plant and Equipment [Line Items]	'
Buildings and improvements/Machinery and equipment	'45 years
Maximum [Member] \| Machinery and Equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Buildings and improvements/Machinery and equipment	'15 years

Description_of_Business_and_Su6

Description of Business and Summary of Significant Accounting Policies - Changes in Accumulated Other Comprehensive Loss by Component (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated Other Comprehensive Income (Loss) by Component, Beginning balance	($23,403)	($25,076)
Net current-period Other Comprehensive Income (Loss)	5,007	1,673
Accumulated Other Comprehensive Income (Loss) by Component, Ending balance	-18,396	-23,403
Cash Flow Hedges [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Net current-period Other Comprehensive Income (Loss)	135	'
Accumulated Other Comprehensive Income (Loss) by Component, Ending balance	135	'
Defined Benefit Pension Plans [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated Other Comprehensive Income (Loss) by Component, Beginning balance	-4,607	-2,485
Net current-period Other Comprehensive Income (Loss)	1,474	-2,122
Accumulated Other Comprehensive Income (Loss) by Component, Ending balance	-3,133	-4,607
Cumulative Foreign Currency Translation [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated Other Comprehensive Income (Loss) by Component, Beginning balance	-18,796	-22,591
Net current-period Other Comprehensive Income (Loss)	3,398	3,795
Accumulated Other Comprehensive Income (Loss) by Component, Ending balance	($15,398)	($18,796)

Acquisitions_Additional_Inform

Acquisitions - Additional Information (Detail)	12 Months Ended		0 Months Ended		12 Months Ended		0 Months Ended	12 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013	Dec. 17, 2013	Dec. 17, 2013	Dec. 31, 2013	Dec. 31, 2013	Jul. 11, 2012	Dec. 31, 2013	Jul. 11, 2012	Dec. 31, 2013	Dec. 31, 2013
	USD ($)	EUR (€)	Svendborg [Member]	Svendborg [Member]	Svendborg [Member]	Svendborg [Member]	Lamiflex [Member]	Lamiflex [Member]	Lamiflex [Member]	Lamiflex [Member]	Bauer [Member]
	Country	Country	USD ($)	EUR (€)		Customer Relationships [Member]	USD ($)		BRL	Customer Relationships [Member]	Convertible Notes Issued [Member]
Business Acquisition [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Business acquisition cash consideration	'	'	$110,200,000	€ 80,100,000	'	'	$7,493,000	'	'	'	'
Cash remaining on the balance sheet upon closing the acquisition	'	'	7,500,000	5,400,000	'	'	'	'	'	'	'
Business acquisition number of countries in which entity operates	7	7	'	'	'	'	'	'	'	'	'
Escrow deposits established for transfer pricing claims	11,600,000	8,500,000	11,600,000	8,500,000	'	'	'	'	'	'	'
Estimated liability for transfer pricing claims by the company	8,100,000	'	8,100,000	'	'	'	'	'	'	'	'
Estimated receivables from transfer pricing claims by the company	'	'	8,100,000	'	'	'	'	'	'	'	'
Business acquisition date	'	'	'	'	17-Dec-13	'	'	11-Jul-12	'	'	'
Percentage of acquisition completed	'	'	'	'	'	'	85.00%	100.00%	'	'	'
Estimated useful lives	'	'	'	'	'	'17 years	'	'	'	'13 years	'
Business acquisition cost	'	'	'	'	'	'	8,600,000	'	17,400,000	'	'
Estimated business acquisition reduction	'	'	'	'	'	'	$1,100,000	'	2,100,000	'	'
Convertible notes issue date	'	'	'	'	'	'	'	'	'	'	7-Mar-11

Acquisitions_Preliminary_Purch

Acquisitions - Preliminary Purchase Price Allocation as of Acquisition Date (Detail)	0 Months Ended
In Thousands, unless otherwise specified	Jul. 11, 2012	Dec. 17, 2013	Dec. 17, 2013
	Lamiflex [Member]	Svendborg [Member]	Svendborg [Member]
	USD ($)	USD ($)	EUR (€)
Business Acquisition [Line Items]	'	'	'
Total Assumed purchase price, excluding acquisition costs	$8,820	$102,096	'
Less: Redeemable noncontrolling interest	1,327	'	'
Total purchase price paid at closing	7,493	110,200	80,100
Cash and cash equivalents	68	7,483	'
Trade receivables, net of amounts pledged	606	21,575	'
Inventories	726	25,452	'
Prepaid and other	48	5,511	'
Property, plant and equipment	3,027	12,216	'
Other assets	108	1,133	'
Intangible assets	4,912	48,893	'
Total assets acquired	9,495	122,263	'
Accounts payable	550	4,833	'
Accrued expenses and other current liabilities	867	9,620	'
Taxes Payable	'	10,254	'
Deferred tax liability	1,934	11,483	'
Other liabilities, including long-term debt	976	'	'
Total liabilities assumed	4,327	36,190	'
Net assets acquired	5,168	86,073	'
Excess of purchase price over fair value of net assets acquired	$3,652	$16,023	'

Acquisitions_Preliminary_Purch1

Acquisitions - Preliminary Purchase Price Allocation as of Acquisition Date (Parenthetical) (Detail) (USD $)	0 Months Ended
In Millions, unless otherwise specified	Jul. 11, 2012	Dec. 17, 2013
	Lamiflex [Member]	Svendborg [Member]
Business Acquisition [Line Items]	'	'
Acquisition costs	$0.40	$2.50

Acquisitions_Amounts_Recorded_

Acquisitions - Amounts Recorded as Intangible Assets (Detail) (USD $)	Dec. 17, 2013	Jul. 11, 2012	Dec. 17, 2013	Dec. 17, 2013
In Thousands, unless otherwise specified	Svendborg [Member]	Lamiflex [Member]	Customer Relationships [Member]	Patents [Member]
			Svendborg [Member]	Svendborg [Member]
Intangible Asset Excluding Goodwill [Line Items]	'	'	'	'
Customer relationships, subject to amortization	'	$4,552	$40,050	$343
Trade names and trademarks, not subject to amortization	8,500	360	'	'
Total intangible assets	$48,893	$4,912	'	'

Acquisitions_Proforma_Amount_o

Acquisitions - Proforma Amount on Acquisition Occurred (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Business Combinations [Abstract]	'	'	'
Total revenues	$803,467	$818,956	$732,837
Net income attributable to Altra Industrial Motion Corp.	$37,750	$22,373	$41,718
Basic earnings per share:	'	'	'
Net income attributable to Altra Industrial Motion Corp.	$1.41	$0.84	$1.57
Diluted earnings per share:	'	'	'
Net income attributable to Altra Industrial Motion Corp.	$1.41	$0.84	$1.56

Inventories_Summary_of_Invento

Inventories - Summary of Inventories (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Inventory Disclosure [Abstract]	'	'
Raw materials	$56,824	$39,902
Work in process	18,432	21,199
Finished goods	68,409	62,675
Inventories, net	$143,665	$123,776

Inventories_Additional_Informa

Inventories - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Inventory [Line Items]	'	'
Portion of total inventory valued by LIFO method	7.50%	10.00%
Change in the inventory balance using FIFO method	$1.60	$0.90
Inventory Valuation by LIFO Method [Member]	'	'
Inventory [Line Items]	'	'
Portion of total inventory valued by LIFO method	7.50%	'
Inventory Valuation Provision [Member]	'	'
Inventory [Line Items]	'	'
Provision for valuation of sales component	$0.70	$0.40

Property_Plant_and_Equipment_S

Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment	$281,074	$243,316
Less-Accumulated depreciation	-123,539	-105,222
Property, plant and equipment, net	157,535	138,094
Land [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment	20,803	13,565
Buildings and Improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment	53,078	38,942
Machinery and Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment	$207,193	$190,809

Property_Plant_and_Equipment_A

Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'
Cash received	'	'	$300,000
Note receivable	'	'	600,000
Note receivable maturity	'	'	'10 years
Accrued interest	'	'	6.00%
Impairment charges	0	'	'
Proceeds from sale of Facility	'	'	1,484,000
Depreciation expense	21,419,000	20,537,000	18,403,000
Stratford, Ontario, Canada Facility [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Sale of facility	'	'	900,000
Mt Pleasant Facility (Member)	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Proceeds from sale of Facility	$578,000	'	'

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Changes in Goodwill (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Goodwill And Intangible Assets Disclosure [Abstract]	'	'
Gross goodwill balance as of January 1	$120,035	$115,609
Adjustments related to the acquisition of Svendborg in 2013 and Lamiflex in 2012	16,023	3,652
Impact of changes in foreign currency and other	91	774
Gross goodwill balance as of December 31	136,149	120,035
Accumulated impairment, January 1	-31,810	-31,810
Impairment charge during period	'	'
Accumulated impairment, December 31	-31,810	-31,810
Net goodwill balance December 31	$104,339	$88,225

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets - Intangibles and Related Accumulated Amortization (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]	'	'
Impact of changes in foreign currency, Cost	($829)	($1,111)
Total intangible assets, Cost	167,132	117,957
Total intangible assets, Accumulated Amortization	48,364	41,859
Tradenames and Trademarks [Member]	'	'
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]	'	'
Intangible assets not subject to amortization, Cost	42,985	34,485
Customer Relationships [Member]	'	'
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]	'	'
Intangible assets subject to amortization, Cost	118,914	78,864
Total intangible assets, Accumulated Amortization	42,645	36,202
Product Technology and Patents [Member]	'	'
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]	'	'
Intangible assets subject to amortization, Cost	6,062	5,719
Total intangible assets, Accumulated Amortization	$5,719	$5,657

Goodwill_and_Intangible_Assets4

Goodwill and Intangible Assets - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill And Intangible Assets [Line Items]	'	'	'
Amortization expense	$6,505,000	$6,839,000	$6,280,000
Weighted average estimated useful life of intangible assets	'11 years	'	'
Estimated Amortization Expense for Intangible Assets [Member]	'	'	'
Goodwill And Intangible Assets [Line Items]	'	'	'
Year 2014	8,800,000	'	'
Year 2015	8,800,000	'	'
Year 2016	8,800,000	'	'
Year 2017	8,800,000	'	'
Year 2018	8,800,000	'	'
Thereafter	$31,800,000	'	'
Minimum [Member]	'	'	'
Goodwill And Intangible Assets [Line Items]	'	'	'
Useful lives of intangible assets	'8 years	'	'
Maximum [Member]	'	'	'
Goodwill And Intangible Assets [Line Items]	'	'	'
Useful lives of intangible assets	'17 years	'	'

Warranty_Costs_Additional_Info

Warranty Costs - Additional Information (Detail)	12 Months Ended
Warranty Costs - Additional Information (Detail)	Dec. 31, 2013
Maximum [Member]	'
Guarantor Obligations [Line Items]	'
Product warranty period	'2 years
Minimum [Member]	'
Guarantor Obligations [Line Items]	'
Product warranty period	'3 months

Warranty_Costs_Changes_in_Carr

Warranty Costs - Changes in Carrying Amount of Accrued Product Warranty Costs (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Guarantees [Abstract]	'	'	'
Balance at beginning of period	$5,625	$4,898	$3,583
Accrued current period warranty costs	2,573	2,386	2,374
Acquired warranty reserves	3,420	'	1,720
Payments and adjustments	-2,879	-1,659	-2,779
Balance at end of period	$8,739	$5,625	$4,898

Income_Taxes_Income_Before_Inc

Income Taxes - Income Before Income Taxes by Domestic and Foreign Locations (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Domestic	$37,640	$18,083	$34,034
Foreign	21,696	16,276	14,397
Income before income taxes	$59,336	$34,359	$48,431

Income_Taxes_Components_of_Pro

Income Taxes - Components of Provision (Benefit) for Income Taxes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current:	'	'	'
Federal	$8,917	$8,370	$4,506
State	698	-3,597	-3,686
Non-US	6,072	6,006	5,057
Current, total	15,687	10,779	5,877
Deferred:	'	'	'
Federal	3,533	-915	7,949
State	378	1,756	-861
Non-US	-447	-1,466	-2,209
Deferred, total	3,464	-625	4,879
Provision (benefit) for income taxes	$19,151	$10,154	$10,756

Income_Taxes_Reconciliation_fr

Income Taxes - Reconciliation from Tax at U.S. Federal Statutory Rate to Company's Provision (Benefit) for Income Taxes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Tax at US federal income tax rate	$20,767	$12,026	$16,957
State taxes, net of federal income tax effect	905	67	1,050
Change in tax rate	-354	-267	-236
Foreign taxes	-224	781	709
Adjustments to accrued income tax liabilities and uncertain tax positions	-52	-1,289	-3,413
Valuation allowance	120	506	-1,644
Intercompany interest	-986	-1,676	-1,178
Tax credits and incentives	-816	-291	-1,243
Domestic manufacturing deduction	-839	-566	-544
Other	630	863	298
Provision (benefit) for income taxes	$19,151	$10,154	$10,756

Income_Taxes_Reconciliation_of

Income Taxes - Reconciliation of Gross Amount of Unrecognized Tax Benefits Excluding Accrued Interest and Penalties (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Balance at beginning of period	$747	$3,523	$6,338
Increases related to prior year tax positions	'	'	'
Decreases related to prior year tax positions	-33	'	-2,289
Increases related to current year tax positions	'	'	'
Settlements	'	-2,689	'
Lapse of statute of limitations	-87	-87	-526
Balance at end of period	$627	$747	$3,523

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail)

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2012

Dec. 31, 2013

USD ($)

EUR (€)

Minimum [Member]

Maximum [Member]

Uncertain Tax Positions [Member]

New York [Member]

Non-U.S. [Member]

Federal and State Tax Credits [Member]

USD ($)

Minimum [Member]

Maximum [Member]

Unrecognized Tax Benefits [Line Items]

Escrow deposits established for transfer pricing claims

$11,600,000

€ 8,500,000

Estimated tax liability for transfer pricing claims by the company

8,100,000

Recognized tax benefit

19,151,000

10,154,000

10,756,000

2,500,000

Tax, reserve

2,300,000

Accrued interest, reserve

1,800,000

Penalties, reserve

500,000

Deferred tax assets related to the federal benefit

1,400,000

Net benefit

3,200,000

Accrued interest and penalties

100,000

200,000

600,000

Offset of accrued interest and penalties due to lapse of statute of limitations

100,000

Total gross amount of interest and penalties

400,000

2,700,000

Net operating loss

28,100,000

22,700,000

Net operating loss, expire year

'2018

'2032

'2014

'2028

Federal and state tax credits

816,000

291,000

1,243,000

2,400,000

Valuation allowance

5,577,000

5,426,000

U.S. or additional non-U.S. taxes, undistributed earnings

$59,900,000

Income_Taxes_Significant_Compo

Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:	'	'
Post-retirement obligations	$1,565	$3,157
Tax credits	2,165	2,040
Expenses not currently deductible	11,788	11,598
Net operating loss carryover	6,376	6,435
Other	546	790
Total deferred tax assets	22,440	24,020
Valuation allowance for deferred tax assets	-5,577	-5,426
Net deferred tax assets	16,863	18,594
Deferred tax liabilities:	'	'
Property, plant and equipment	20,065	19,892
Intangible assets	25,090	14,969
Basis difference - convertible debt	11,064	10,212
Goodwill	3,813	2,308
Total deferred liabilities	60,032	47,381
Net deferred tax liabilities	$43,169	$28,787

Pension_and_Other_Employee_Ben2

Pension and Other Employee Benefits - Reconciliation of Benefit Obligation, Fair Value of Plan Assets and Funded Status of Respective Defined Benefit (Pension) and Postretirement Benefit Plans (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Plans, Postretirement and Other Employee Benefits [Line Items]	'	'	'
Employer contributions	$3,700	$3,500	'
Amounts Recognized in the balance sheet consist of:	'	'	'
Total	-8,025	-14,529	'
Pension Benefits [Member]	'	'	'
Pension Plans, Postretirement and Other Employee Benefits [Line Items]	'	'	'
Obligation at beginning of period	34,629	29,415	'
Assumed Bauer pension liability	'	'	'
Service cost	248	179	167
Interest cost	1,250	1,381	1,389
Curtailments, settlements and special termination benefits	'	'	'
Actuarial (gains) losses	-2,969	4,574	'
Foreign exchange effect	343	153	'
Benefits paid	-1,286	-1,073	'
Obligation at end of period	32,215	34,629	29,415
Fair value of plan assets, beginning of period	20,100	16,519	'
Assumed Bauer plan assets	'	'	'
Actual return on plan assets	182	2,035	'
Employer contributions	5,194	2,619	'
Benefits paid	-1,286	-1,073	'
Fair value of plan assets, end of period	24,190	20,100	16,519
Funded status	-8,025	-14,529	'
Amounts Recognized in the balance sheet consist of:	'	'	'
Non current assets	'	'	'
Current liabilities	'	'	'
Non-current liabilities	-8,025	-14,529	'
Total	($8,025)	($14,529)	'

Pension_and_Other_Employee_Ben3

Pension and Other Employee Benefits - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Accumulated benefit obligation	$32,200,000	$34,600,000	'
Non-U.S. pension liabilities recognized	7,700,000	7,600,000	'
Accumulated other comprehensive loss	1,500,000	2,100,000	'
Accumulated other comprehensive loss, net of tax	800,000	1,400,000	'
Expected long-term rate of return on assets	5.25%	'	'
Defined contribution plans, maximum employee contribution	75.00%	'	'
Percent of contribution made	6.00%	'	'
Contribution description	'The Company makes matching contributions equal to half of the first six percent of salary contributed by each employee	'	'
Defined benefit plan, supplementary contributions by employer	3,700,000	3,500,000	'
U.S. Pension Plan 2013 [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Minimum cash contribution to pension plan	5,000,000	'	'
U.S. Pension Plan 2014 [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Minimum cash contribution to pension plan	0	'	'
U.S. Pension Plan 2015 [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Minimum cash contribution to pension plan	0	'	'
U.S. Pension Plan 2016 [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Minimum cash contribution to pension plan	300,000	'	'
U.S. Pension Plan 2017 [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Minimum cash contribution to pension plan	300,000	'	'
U.S. Pension Plan 2018 [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Minimum cash contribution to pension plan	300,000	'	'
Other Post Retirement Benefit Plans [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Accumulated benefit obligation	200,000	200,000	'
Other Post Retirement Benefit Plans [Member] \| Maximum [Member]	'	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'	'
Income recorded by the company	$100,000	$100,000	$100,000

Pension_and_Other_Employee_Ben4

Pension and Other Employee Benefits - Discount Rate Used in Computation of Respective Benefit Obligations (Detail) (Pension Benefits [Member])	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Pension Benefits [Member]	'	'
Pension Plans, Postretirement and Other Employee Benefits [Line Items]	'	'
Discount rate used in benefit obligation	4.60%	3.75%

Pension_and_Other_Employee_Ben5

Pension and Other Employee Benefits - Components of Net Periodic Benefit Cost (Detail) (Pension Benefits [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Benefits [Member]	'	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'	'
Service cost	$248	$179	$167
Interest cost	1,250	1,381	1,389
Recognized net actuarial loss	'	'	'
Expected return on plan assets	-1,080	-1,083	-1,050
Settlement/Curtailment/Special Termination Benefit	'	'	'
Amortization	175	105	39
Net periodic benefit (income) cost	$593	$582	$545

Pension_and_Other_Employee_Ben6

Pension and Other Employee Benefits - Economic Assumptions Used in Computation of Respective Net Periodic Benefit Cost (Detail) (Pension Benefits [Member])	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Pension Benefits [Member]	'	'	'
Economic Assumptions Used In Measuring Of Fair Value Securitized Loans [Line Items]	'	'	'
Discount rate	3.75%	4.75%	5.50%
Expected return on plan assets	5.25%	6.25%	7.75%
Compensation rate increase	'	'	'

Pension_and_Other_Employee_Ben7

Pension and Other Employee Benefits - Schedule Fair Value of Pension Plan Assets (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2013
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total equity	$4,819	'
Total fixed income	14,341	23,512
Total assets at fair value	20,100	24,190
U.S. Companies [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total equity	4,522	'
International Companies [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total equity	297	'
U.S. Government [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total fixed income	820	2,787
Investment Grade [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total fixed income	8,738	17,091
High Yield [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total fixed income	3,151	3,634
Other Credit [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total fixed income	1,632	'
Other [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total assets at fair value	328	338
Cash and Cash Equivalents [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Total assets at fair value	$612	$340

Pension_and_Other_Employee_Ben8

Pension and Other Employee Benefits - Schedule of Asset Allocations for Funded Retirement Plan (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Global Developed Equity [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Actual	0.00%	5.00%
Target, Minimum	0.00%	'
Target, Maximum	0.00%	'
Investment Grade Bonds [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Actual	84.00%	48.00%
Target, Minimum	20.00%	'
Target, Maximum	100.00%	'
High Yield Bonds [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Actual	15.00%	16.00%
Target, Minimum	0.00%	'
Target, Maximum	25.00%	'
Cash [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Actual	1.00%	3.00%
Target, Minimum	0.00%	'
Target, Maximum	5.00%	'
Emerging Market Debt [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Actual	0.00%	3.00%
Target, Minimum	0.00%	'
Target, Maximum	0.00%	'
Dynamic Asset Allocation/Alternatives [Member]	'	'
Defined Benefit Pension Plan With Accumulated Benefit Obligation In Excess Of Fair Value Of Plan Assets [Line Items]	'	'
Actual	0.00%	25.00%
Target, Minimum	0.00%	'
Target, Maximum	0.00%	'

Pension_and_Other_Employee_Ben9

Pension and Other Employee Benefits - Summary of Amounts of Expected Benefit Payments (Detail) (Pension Benefits [Member], USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2013
Pension Benefits [Member]	'
Defined Benefit Plan, Expected Future Benefit Payments, Maturity [Line Items]	'
2014	$1,153
2015	1,309
2016	1,370
2017	1,399
2018	1,464
Thereafter	$7,895

LongTerm_Debt_Outstanding_Debt

Long-Term Debt - Outstanding Debt Obligations (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]	'	'
Total debt	$294,435	$266,901
Less: debt discount, net of accretion	-16,163	-19,306
Total debt, net of unaccreted discount	278,272	247,595
Less current portion of long-term debt	16,924	9,135
Total long-term debt	261,348	238,460
Revolving Credit Facility [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	41,198	79,304
Convertible Notes [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	85,000	85,000
Term Loan Facility [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	163,245	100,000
Equipment Loan [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	4,155	1,100
Mortgages [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	659	963
Capital Leases [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	178	99
Other [Member]	'	'
Debt Instrument [Line Items]	'	'
Total debt	'	$435

LongTerm_Debt_Additional_Infor

Long-Term Debt - Additional Information (Detail)

12 Months Ended

1 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Nov. 20, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Nov. 30, 2012

Dec. 31, 2013

Nov. 30, 2012

Dec. 31, 2013

Nov. 30, 2012

Dec. 31, 2013

Nov. 30, 2012

Dec. 31, 2013

Nov. 30, 2012

Dec. 31, 2013

Nov. 30, 2012

Dec. 31, 2013

Dec. 31, 2012

Nov. 30, 2012

Dec. 31, 2013

Sep. 01, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Nov. 30, 2009

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

USD ($)

Initial Conversion Price [Member]

Term Loan [Member]

Revolving Credit Facility [Member]

Additional Term Loan [Member]

Minimum [Member]

Maximum [Member]

Term Loan Facility [Member]

Revolving Credit Agreement [Member]

Convertible Debt [Member]

Convertible Notes [Member]

Senior Secured Notes [Member]

Mortgages [Member]

Capital Leases [Member]

Equipment and Working Capital Notes [Member]

USD ($)

EUR (€)

Eurodollar Loan [Member]

ABR Based Loans [Member]

USD ($)

Eurodollar Loan [Member]

ABR Based Loans [Member]

USD ($)

EUR (€)

USD ($)

EUR (€)

USD ($)

CNY

Minimum [Member]

Maximum [Member]

Debt Instrument [Line Items]

Availability under credit facility agreement

$94,375,000

€ 50,000,000

$100,000,000

$200,000,000

Aggregate additional term loans

150,000,000

Credit facility maturity date

'November 20, 2017

'December 6, 2018

Debt instrument, maturity date

20-Nov-17

6-Dec-18

1-Mar-31

1-Dec-16

Applicable margins for loans

1.38%

0.38%

1.88%

0.88%

Outstanding on Revolving Credit Facility

41,200,000

79,300,000

Letters of credit outstanding

9,800,000

7,600,000

Amount available under credit facility

149,000,000

113,100,000

Percentage of capital stock not included in collateral

65.00%

Coupon interest rate

2.75%

Proceeds from the offering

81,300,000

Adjustment of shares

36.0985

Principal amount of notes

1,000

Conversion price per share

$27.09

$27.70

Percentage of sale price of common stock

130.00%

Consecutive trading days

'30 days

'20 days

Number of business day period

'5 days

Number of consecutive trading days in measurement period

'10 days

Percentage of measurement period

97.00%

Percentage of convertible notes redeemable

100.00%

Convertible notes redeemable period one

1-Mar-18

Convertible notes redeemable period two

1-Mar-21

Convertible notes redeemable period three

1-Mar-26

Conversion price redemption exceed

130.00%

Total debt

85,000,000

200,000

100,000

Debt component in note payable

60,500,000

Equity component in note payable

24,500,000

Discount rate for debt component

8.25%

Debt issuance cost

4,100,000

4,300,000

3,700,000

Adjustments to additional paid-in capital of convertible debt

1,000,000

Debt issuance cost, amortized

2,700,000

Effective interest rate of Senior Secured Notes

8.50%

8.75%

Face value of Senior Notes

210,000,000

Company issued Senior Secured Notes

2.75%

8.13%

Deferred financing costs

6,700,000

Company repurchased Senior Secured Notes

12,000,000

Repayments of Senior Debt with premium

300,000

Original issue discount of Senior Secured Notes

400,000

Redemption of remaining Senior Secured Notes

198,000,000

Pre-payment premiums

11,400,000

Deferred financing fees and original issue discount

4,400,000

Outstanding letters of credit

90.00%

Available to borrow loan amount

6,300,000

38,500,000

Interest rate

5.75%

5.04%

6.69%

Line of credit outstanding loan amount

4,100,000

25,400,000

Description about maturity date of debt instrument

'The note is due in installments from 2014 through 2016

Mortgage remaining principal balance

700,000

500,000

1,000,000

700,000

Mortgage loan payable term

'3 years

Borrowings under overdraft agreements

LongTerm_Debt_Carrying_Amount_

Long-Term Debt - Carrying Amount of Debt (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]	'	'
Carrying value of debt	$261,348,000	$238,460,000
Convertible Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Principal amount of debt	85,000,000	'
Unamortized discount	16,163,000	'
Carrying value of debt	$68,837,000	'

LongTerm_Debt_Interest_Expense

Long-Term Debt - Interest Expense Associated with Convertible Notes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Contractual coupon rate of interest	$2,338
Accretion of Convertible Notes discount and amortization of deferred financing costs	3,494
Interest expense for the Convertible Notes	$5,832

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended
	Oct. 29, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 20, 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Common stock, shares authorized	'	90,000,000	90,000,000	'	'
Common stock, shares outstanding	'	26,819,795	26,724,349	'	'
Preferred stock, shares authorized	'	10,000,000	10,000,000	'	10,000,000
Preferred stock, shares issued	'	0	0	'	'
Preferred stock, shares outstanding	'	0	0	'	'
Compensation expense	'	$3,200,000	$2,700,000	$2,500,000	'
Compensation expense, net of tax	'	2,900,000	1,800,000	1,700,000	'
Unrecognized compensation cost	'	3,000,000	'	'	'
Weighted average remaining period	'	'2 years	'	'	'
Fair market value of the shares	'	2,400,000	3,200,000	3,300,000	'
Stock price	'	$34.22	'	'	'
Cash dividend	$0.10	$0.38	$0.16	'	'
Dividend paid	'	2,696,000	'	'	'
Dividends payable date of record	'	18-Dec-13	'	'	'
Dividend paid date	'	3-Jan-14	'	'	'
Restricted Stock [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Intrinsic value of stock awards	'	$5,100,000	'	'	'
Maximum [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Restricted shares for vesting period	'	'5 years	'	'	'

Stockholders_Equity_Schedule_o

Stockholders' Equity - Schedule of Activity of Company's Restricted Stock Grants (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Restricted shares unvested, beginning balance	162,586
Shares granted	128,365
Shares for which restrictions lapsed	-141,316
Restricted shares unvested, ending balance	149,635
Weighted-Average Grant Date Fair Value, beginning balance	$18.67
Weighted-Average Grant Date Fair Value, Shares granted	$24.58
Weighted-Average Grant Date Fair Value, Shares for which restrictions lapsed	$21.55
Weighted-Average Grant Date Fair Value, ending balance	$23.02

Concentrations_of_Credit_Segme2

Concentrations of Credit, Segment Data and Workforce - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Customer	Customer	Customer
Concentration Risk [Line Items]	'	'	'
Sales contract payments due period	'30 days	'	'
Number of operating segments	3	'	'
Number of reportable segments	1	'	'
Number of operating segments expected to have similar long-term average gross profit margins	3	'	'
Net assets of foreign subsidiaries	138.7	117	'
Percentage of labor force is represented by collective bargaining agreements	23.00%	'	'
Number of collective bargaining agreements	4	'	'
Collective Bargaining, July 2014 [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Collective bargaining agreements, expire date	'2014-07	'	'
Collective Bargaining, October 2014 [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Collective bargaining agreements, expire date	'2014-10	'	'
Collective Bargaining, June 2014 [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Collective bargaining agreements, expire date	'2014-06	'	'
Collective Bargaining, October 2016 [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Collective bargaining agreements, expire date	'2016-10	'	'
Sales [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Maximum revenue percentage from any one customer	10.00%	10.00%	10.00%
Number of customers representing over 10% of total sales	0	0	0
The Americas (Primarily U.S.) [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Percentage of labor force is represented by collective bargaining agreements	10.00%	'	'
Europe [Member]	'	'	'
Concentration Risk [Line Items]	'	'	'
Percentage of labor force is represented by collective bargaining agreements	57.00%	'	'

Concentrations_of_Credit_Segme3

Concentrations of Credit, Segment Data and Workforce - Net Sales to Third Parties and Property, Plant and Equipment by Geographic Region (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 31, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Concentration Risk [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	$180,530	$175,443	$181,095	$185,150	$177,174	$174,488	$187,943	$192,385	$722,218	$731,990	$674,812
Property, plant and equipment, net	157,535	'	'	'	138,094	'	'	'	157,535	138,094	'
North America [Member]	'	'	'	'	'	'	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	454,115	469,554	442,931
Property, plant and equipment, net	87,573	'	'	'	88,051	'	'	'	87,573	88,051	'
Europe [Member]	'	'	'	'	'	'	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	216,636	216,485	191,768
Property, plant and equipment, net	54,533	'	'	'	35,319	'	'	'	54,533	35,319	'
Asia and the Rest of the World [Member]	'	'	'	'	'	'	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Net sales	'	'	'	'	'	'	'	'	51,467	45,951	40,113
Property, plant and equipment, net	$15,429	'	'	'	$14,724	'	'	'	$15,429	$14,724	'

Restructuring_Asset_Impairment2

Restructuring, Asset Impairment, and Transition Expenses - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
				2012 Altra Plan [Member]	2012 Altra Plan [Member]	2012 Altra Plan [Member]
						Subsequent Event [Member]
Restructuring Cost and Reserve [Line Items]	'	'	'	'	'	'
Restructuring charges	$1,111	$3,196	$0	$1,111	$3,196	'
Expected restructuring expenses	'	'	'	'	'	$0

Restructuring_Asset_Impairment3

Restructuring, Asset Impairment, and Transition Expenses - Summary of Total Restructuring Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Expenses	'	'	'
Total restructuring expenses	$1,111	$3,196	$0
2012 Altra Plan [Member]	'	'	'
Expenses	'	'	'
Moving and relocation	-21	55	'
Severance	1,103	2,934	'
Other	29	207	'
Total cash expenses	1,111	3,196	'
Loss on disposal of fixed assets	'	'	'
Total restructuring expenses	$1,111	$3,196	'

Restructuring_Asset_Impairment4

Restructuring, Asset Impairment, and Transition Expenses - Reconciliation of Accrued Restructuring Costs (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Related Party Transactions [Abstract]	'	'	'
Beginning Balance	$2,815	$90	'
Restructuring expense incurred	1,111	3,196	0
Cash payments	-3,497	-471	'
Non-cash loss on impairment of fixed assets	'	'	'
Ending Balance	$429	$2,815	$90

Derivative_Financial_Instrumen2

Derivative Financial Instruments - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013	Apr. 30, 2013
	Dec. 31, 2013	Interest Rate Swap [Member]	Interest Rate Swap [Member]
Debt Instrument [Line Items]	'	'	'
Outstanding borrowings	'	$92,500,000	$92,500,000
Fixed Rate	'	0.63%	0.63%
Ineffectiveness associated with the swap	$0	'	'

Derivative_Financial_Instrumen3

Derivative Financial Instruments - Summary of Swap Recognized in Other Non-Current Assets and in Other Comprehensive Income (Loss) (Detail) (Interest Rate Swap [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Apr. 30, 2013	Dec. 31, 2012
Interest Rate Swap [Member]	'	'	'
Derivative [Line Items]	'	'	'
Effective Date	30-Apr-13	'	'
Notional Amount	$92,500	$92,500	'
Fixed Rate	0.63%	0.63%	'
Maturity	30-Nov-16	'	'
Fair Value	$213	'	'

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail)	12 Months Ended							12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
	USD ($)	USD ($)	USD ($)	Inventory [Member]	Inventory [Member]	Inventory [Member]	Inventory [Member]	Maximum [Member]
				Subsequent Event [Member]	Subsequent Event [Member]	Subsequent Event [Member]	Subsequent Event [Member]
				USD ($)	EUR (€)	USD ($)	EUR (€)
Schedule Of Commitments And Contingencies [Line Items]	'	'	'	'	'	'	'	'
Term of lease	'	'	'	'	'	'	'	'10 years
Net rent expense under operating leases	$8,800,000	$7,800,000	$6,900,000	'	'	'	'	'
Minimum purchase contracts	'	'	'	4,900,000	3,600,000	4,900,000	3,600,000	'
Aggregate amount of settlement	$0.09	'	'	'	'	'	'	'

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Rent Obligations under Non-Cancelable Operating and Capital Leases (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
2014, Operating Leases	$7,618
2015, Operating Leases	6,225
2016, Operating Leases	4,847
2017, Operating Leases	2,594
2018, Operating Leases	1,892
Thereafter, Operating Leases	6,970
Total lease obligations, Operating Leases	30,146
2014, Capital Leases	147
2015, Capital Leases	28
2016, Capital Leases	8
2017, Capital Leases	6
2018, Capital Leases	'
Thereafter, Capital Leases	'
Total lease obligations, Capital Leases	189
Less amounts representing interest, Capital Leases	-8
Present value of minimum capital lease obligations, Capital Leases	$181

Unaudited_Quarterly_Results_of2

Unaudited Quarterly Results of Operations - Schedule of Quarterly Results of Operations (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 31, 2012	Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Net sales	$180,530	$175,443	$181,095	$185,150	$177,174	$174,488	$187,943	$192,385	$722,218	$731,990	$674,812
Gross Profit	51,805	53,658	54,419	55,499	53,862	52,011	56,002	56,673	215,381	218,548	196,418
Net income attributable to Altra Industrial Motion Corp.	$7,205	$10,501	$10,689	$11,880	($5,379)	$8,547	$10,609	$10,516	$40,275	$24,293	$37,675
Earnings per share - Basic attributable to Altra Industrial Motion Corp. Net income	$0.27	$0.39	$0.40	$0.44	($0.20)	$0.32	$0.40	$0.40	$1.50	$0.91	$1.42
Earnings per share - Diluted attributable to Altra Industrial Motion Corp. Net income	$0.27	$0.39	$0.40	$0.44	($0.20)	$0.32	$0.40	$0.39	$1.50	$0.91	$1.41

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended		3 Months Ended
	Oct. 29, 2013	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014	Feb. 28, 2014
				Subsequent Event [Member]	Equity Incentive Plan [Member]
					Subsequent Event [Member]
Subsequent Event [Line Items]	'	'	'	'	'
Restricted common stock shares being approved	'	'	'	'	92,470
Dividend per share	$0.10	$0.38	$0.16	$0.10	'
Dividend payable date	'	'	'	3-Apr-14	'
Dividend record date	'	18-Dec-13	'	18-Mar-14	'

Schedule_II_Valuation_and_Qual

Schedule II - Valuation and Qualifying Accounts (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Valuation And Qualifying Accounts [Abstract]	'	'	'
Balance at Beginning of Period	$2,560	$1,092	$1,111
Additions	733	1,675	696
Deductions	-1,048	-207	-715
Balance at End of Period	$2,245	$2,560	$1,092