Finance Receivables (Narratives) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2013
Finance Receivables
Financing receivable credit quality additional information	We generally seek investments in facilities that we believe are critical to a tenant’s business and that we believe have a low risk of tenant defaults. At both June 30, 2013 and December 31, 2012, none of our finance receivables were past due and we had not established any allowances for credit losses.
Financing receivable credit quality range of dates ratings updated	second quarter of 2013
Reclassification from direct financing lease	$ 5.6
Proceeds from sale of direct financing lease	5.5
Gain (loss) on direct financing lease	$ (0.3)

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Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 29

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953659-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 30

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953664-111524

+ Details

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- Definition

Includes a disclosure detailing the range of dates that the consumer credit scores were last updated.

+ References

+ Details

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- Definition

The cash inflow associated with the sale of receivables arising from the financing of goods and services.

+ References

No definition available.

+ Details

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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of finance receivable that were sold during the reporting period. This element refers to the gain (loss) and not to the cash proceeds of the sales.

+ References

No definition available.

+ Details

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- Definition

Increase decrease in net investments in direct financing lease during the period.

+ References

No definition available.

+ Details

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Balance Type:	debit
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