Note 10 - Coal Mining Liability (Details) In Millions, unless otherwise specified	Dec. 27, 2014 USD ($)	Dec. 27, 2014 EUR (€)	Dec. 28, 2013 USD ($)	Dec. 28, 2013 EUR (€)
Other Liabilities and Financial Instruments Subject to Mandatory Redemption [Abstract]
Loss Contingency, Accrual, Noncurrent	$ 2.4	€ 1.9	$ 3.1	€ 2.2

Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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