Note 9 - Fair Value of Financial Instruments (Details) $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($)
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	$ 2.1
Minimum [Member]
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Mortgage Loans on Real Estate, Interest Rate	3.10%
Maximum [Member]
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Mortgage Loans on Real Estate, Interest Rate	3.60%
Weighted Average [Member]
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Mortgage Loans on Real Estate, Interest Rate	3.40%
Fair Value, Inputs, Level 2 [Member] \| Senior Notes 2024 [Member]
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Long-term Debt, Fair Value	$ 239.5
Fair Value, Inputs, Level 2 [Member] \| Senior Notes 2023 [Member]
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Long-term Debt, Fair Value	263.0
Fair Value, Inputs, Level 3 [Member] \| Mortgages [Member]
Note 9 - Fair Value of Financial Instruments (Details) [Line Items]
Notes Payable, Fair Value Disclosure	$ 62.8

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

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- Definition

Fair value portion of notes payable.

+ 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 210.5-02.19,20,22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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