Borrowings (Details 3) (USD $)	6 Months Ended
Jun. 30, 2011
Remaining scheduled principal repayments
Term loan, amount	$ 25,469,000
Master lease facility, amount	5,000,000
Term of capital lease (in months)	48
Ending purchase price of underlying equipment	1
Probable purchase price of underlying equipment	1,000,000
Master Loan and Security Agreement (Term Loan Agreement)
Term Loan
Term of Term Loan Agreement (in years)	4
Rate of additional interest payable (as a percent)	3.00%
Monthly principal installments	530,600
Interest, margin over base rate (as a percent)	3.00%
Interest, base rate	one month London Interbank Offered Rate (LIBOR)
Remaining scheduled principal repayments
2011	3,184,000
2012	6,367,000
2013	6,367,000
2014	6,367,000
2015	3,184,000
Term loan, amount	$ 25,469,000

Represents the purchase price of the underlying equipment at the end of the capital lease term.

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- Definition

Represents the probable purchase price of the underlying equipment under the capital lease.

+ Details

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- Definition

The term of the capital lease.

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- Definition

Represents the additional interest rate payable in the event of a default of the terms of the Term Loan Agreement.

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- Definition

The term of the debt instrument.

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- Definition

Amount of long-term debt maturing within the first full fiscal year following the date of the latest balance sheet presented in the financial statements.

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- Definition

Amount of long-term debt maturing within the fourth full fiscal year following the date of the latest balance sheet presented in the financial statements.

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Amount of long-term debt maturing within the remainder of the fiscal year following the date of the latest balance sheet presented in the financial statements.

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- Definition

Amount of long-term debt maturing within the second full fiscal year following the date of the latest balance sheet presented in the financial statements.

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Amount of long-term debt maturing within the third full fiscal year following the date of the latest balance sheet presented in the financial statements.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 7
-Section 03
-Paragraph 16

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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The percentage points added to the reference rate to compute the variable rate on the debt instrument.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of the required periodic payments applied to principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 7
-Section 03
-Paragraph 16

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 16
-Article 9

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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