Cost method investment ownership percentage.

No definition available.

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ 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 210.5-02.12)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 35

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=29638308&loc=d3e40346-111594

+ Details

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 35

-Paragraph 32

-URI http://asc.fasb.org/extlink&oid=35687916&loc=d3e32787-111569

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-Name Accounting Standards Codification

-Topic 350

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-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

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-Name Accounting Standards Codification

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-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

+ Details

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

+ Details

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Summary of Significant Accounting Policies - Asset Impairments - Additional Information (Detail) (USD $)	8 Months Ended	12 Months Ended
	Dec. 31, 2014	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment incurred	$ 0us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss	$ 0us-gaap_GoodwillImpairmentLoss
Impairment of equity method investment				10,680,000
Investment impairment charge	2,320,000us-gaap_ImpairmentOfInvestments			10,680,000us-gaap_ImpairmentOfInvestments
Carrying amount of cost method investment	14,432,000us-gaap_CostMethodInvestments	16,752,000us-gaap_CostMethodInvestments	16,486,000us-gaap_CostMethodInvestments
Recycle Rewards Inc [Member]
Summary Of Significant Accounting Policies [Line Items]
Outstanding common stock percentage	6.7
Investment impairment charge	2,320,000
Carrying amount of cost method investment	2,160,000
Eastern Region [Member]
Summary Of Significant Accounting Policies [Line Items]
Reporting units exceeded their carrying values	15.00%
Western Region [Member]
Summary Of Significant Accounting Policies [Line Items]
Reporting units exceeded their carrying values	28.20%
Recycling [Member]
Summary Of Significant Accounting Policies [Line Items]
Reporting units exceeded their carrying values	20.80%
Other [Member] \| Customer Solutions [Member]
Summary Of Significant Accounting Policies [Line Items]
Reporting units exceeded their carrying values	83.30%
GreenFiber [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill impairment incurred				5,090,000
Impairment of equity method investment				$ 10,680,000