Name:	usap_AcquisitionsAdditionalTextualAbstract
Namespace Prefix:	usap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	usap_AcquisitionsTextualAbstract
Namespace Prefix:	usap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The pro forma ratio calculated by dividing the pro forma amount of income tax expense attributable to continuing operations for the period by pro forma pre-tax income from continuing operations as if the business combination had been completed at the beginning of the period.

+ References

No definition available.

+ Details

Name:	usap_BusinessAcquisitionProFormaEffectiveTaxRate
Namespace Prefix:	usap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt issued to finance significant acquisition.

+ References

No definition available.

+ Details

Name:	usap_DebtIssuedToFinanceAcquisition
Namespace Prefix:	usap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Escrow agreement expiration date.

+ References

No definition available.

+ Details

Name:	usap_EscrowAgreementExpirationDate
Namespace Prefix:	usap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_BusinessAcquisitionCostOfAcquiredEntityPurchasePrice
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e845-128460

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Acquisition Date

-URI http://asc.fasb.org/extlink&oid=6919109

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e848-128460

+ Details

Name:	us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 59

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.10)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_EscrowDeposit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Acquisition (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended		1 Months Ended	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Aug. 31, 2011 North Jackson Facility [Member]	Sep. 30, 2011 North Jackson Facility [Member]	Sep. 30, 2011 North Jackson Facility [Member]	Aug. 18, 2011 North Jackson Facility [Member]	Aug. 18, 2011 North Jackson Facility [Member] Revolving credit facility [Member]	Aug. 18, 2011 North Jackson Facility [Member] Term loan [Member]	Aug. 18, 2011 North Jackson Facility [Member] Convertible promissory notes [Member]
Acquisitions (Textual) [Abstract]
Company acquired substantially all the assets of Patriot Special Metals, Inc. and RSM Real Estate Holding, Inc.				Aug. 18, 2011
Aggregrate purchase price							$ 111.3
Debt issued to finance acquisition								40.0	40.0	20.0
Pro forma effective tax rate					36.40%	36.40%
Acquisitions (Additional Textual) [Abstract]
Escrow agreement with the sellers		2.5
Escrow agreement with the sellers expiry date		Feb. 18, 2013
Acquisition related costs	$ 1.1		$ 2.1
Fair value assigned to the non-compete agreement is subject to amortization period		5 years