Note 1 - Description of Business and Basis of Presentation (Details Textual) $ in Millions		3 Months Ended	6 Months Ended
May 01, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)
Number of States in which Entity Operates		21	21
Number of Reportable Segments			1
Reduction in Expense Due to Change in Capitalized Labor Accounting Estimate [Member]
Change in Accounting Estimate, Impact		$ 5.1	$ 11.0
New Wave [Member]
Payments to Acquire Businesses, Gross	$ 741.0

The impact of a change in an accounting estimate to the reporting entity's financial statements.

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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- Details

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