The estimated minimum amount of possible loss from the contingency.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Environmental and legal matters (Details) (USD $)	0 Months Ended
Environmental and legal matters (Details) (USD $)	Nov. 26, 2014	Mar. 20, 2014 subsidiaries	Mar. 20, 2014 companies	Mar. 20, 2014 individuals	Mar. 20, 2014 current_employees	Mar. 20, 2014 former_employee	Feb. 19, 2014
Environmental Remediation Obligations [Abstract]
Loss Contingency, Number of Defendants		2	18	100	2	1
Loss Contingency, Range of Possible Loss, Minimum							$ 100,000
Loss Contingency, Settlement Amount Paid	$ 390,733us-gaap_LitigationSettlementAmount