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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=75025870&loc=d3e40691-111596

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=75027002&loc=d3e40346-111594

+ Details

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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 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

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Period Type:	duration

- 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

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=98514028&loc=d3e3602-108585

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e25351-111560

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Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Details

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- Details

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- Details

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- Details

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- Details

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Asset Impairments (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Goodwill impairment incurred	$ 0	$ 0	$ 0
Investment impairment charge	0	0	2,099,000
Carrying amount of cost method investment	$ 12,333,000	$ 12,333,000
Recycle Rewards Inc
Segment Reporting Information [Line Items]
Outstanding common stock percentage	5.60%
Investment impairment charge			1,090,000
Carrying amount of cost method investment	$ 1,069,000
GreenerU Inc
Segment Reporting Information [Line Items]
Outstanding common stock percentage	5.20%
Investment impairment charge			691,000
Carrying amount of cost method investment	$ 309,000
Agreen Energy LLC
Segment Reporting Information [Line Items]
Outstanding common stock percentage	17.00%
Bgreen Energy LLC
Segment Reporting Information [Line Items]
Outstanding common stock percentage	16.20%
Agreen And Bgreen
Segment Reporting Information [Line Items]
Investment impairment charge			$ 318,000
Carrying amount of cost method investment	$ 297,000
Eastern
Segment Reporting Information [Line Items]
Reporting units exceeded their carrying values	83.60%
Western
Segment Reporting Information [Line Items]
Reporting units exceeded their carrying values	74.60%
Recycling
Segment Reporting Information [Line Items]
Reporting units exceeded their carrying values	74.60%
Other
Segment Reporting Information [Line Items]
Reporting units exceeded their carrying values	74.60%