Leases (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 784
Charged to earnings	867
Deductions	(748)
Ending Balance	$ 903

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Period Type:	duration

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (c)(1)

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Charge to expense for financing receivables that are expected to be uncollectible.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reduction to the allowance for credit losses related to financing receivables deemed uncollectible.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration