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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Asset Impairments (Detail) - USD ($) | 12 Months Ended
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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% |  |

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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=75025870&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=75027002&loc=d3e40346-111594 + Details
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