Note 5 - Leasing Arrangements (Details Textual) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Property Subject to or Available for Operating Lease, Gross	$ 29.3	$ 38.9
Property Subject to or Available for Operating Lease, Accumulated Depreciation	$ 15.0	$ 18.5

The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6453916&loc=d3e41460-112716

Name:	us-gaap_PropertySubjectToOrAvailableForOperatingLeaseAccumulatedDepreciation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant