Net Investment in Sales-Type Leases sales type lease - from min payments to non current investment (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Capital Leased Assets [Line Items]
Net minimum lease payments to be received	$ 19,665,000	$ 15,063,000
Less unearned interest income portion	1,205,000	1,229,000
Net investment in sales-type leases	18,460,000	13,834,000
Less current portion	5,232,000	5,049,000
Non-current net investment in sales-type leases (2)	13,228,000	8,785,000
Allowance for Notes, Loans and Financing Receivable, Current	500,000	100,000
Allowance for Notes, Loans and Financing Receivable, Noncurrent	$ 100,000	$ 100,000

A valuation allowance relating to a written agreement to receive money (at a specified future date(s) within one year from the reporting date (or the normal operating cycle, whichever is longer), consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 4

-Article 5

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A valuation allowance relating to a written agreement to receive money (at a specified future date(s) more than one year from the reporting date, consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible.

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- Definition

The net amount due within one year of the balance sheet date or the normal operating cycle, if longer, consisting of: (a) minimum lease payments on sales type leases and (b) unguaranteed residual value; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

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- Definition

The net amount due after one year of the balance sheet date or beyond the normal operating cycle, if longer, consisting of: (a) minimum lease payments on sales type leases, and (b) unguaranteed residual value; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

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The net investment in sales type leases as of the balance sheet date consisting of: (a) minimum lease payments on sales type leases and (b) unguaranteed residual value; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

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The remaining (unamortized) difference between the gross investment in a sales-type lease and the cost or carrying amount of the leased property as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph a(i)(d)

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Amount of remaining payments as of the balance sheet date that lessees are obligated to make or can be required to make under sales-type leases, including any guarantee of residual value and executory costs. The amount also includes any guaranteed rental payments by an unrelated third-party provided that are financially capable of making such payments.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 5

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-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.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph a(i)(a)

-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.

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-Name Accounting Standards Codification

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