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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Asset Impairments (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Segment Reporting Information [Line Items] |  |  |
Goodwill impairment incurred | $ 0 | $ 0 | $ 0
Impairment of investments | 1,069,000 | 0 | $ 0
Carrying amount of cost method investment | $ 11,264,000 | $ 12,333,000 |
Recycle Rewards Inc |  |  |
Segment Reporting Information [Line Items] |  |  |
Outstanding common stock percentage | 6.80% |  |
Impairment of investments | $ 1,069,000 |  |
Carrying amount of cost method investment | $ 0 |  |
GreenerU Inc |  |  |
Segment Reporting Information [Line Items] |  |  |
Outstanding common stock percentage | 5.20% |  |
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] |  |  |
Carrying amount of cost method investment | $ 297,000 |  |
Eastern |  |  |
Segment Reporting Information [Line Items] |  |  |
Reporting units exceeded their carrying values (as a percent) | 21.50% |  |
Western |  |  |
Segment Reporting Information [Line Items] |  |  |
Reporting units exceeded their carrying values (as a percent) | 21.50% |  |
Recycling |  |  |
Segment Reporting Information [Line Items] |  |  |
Reporting units exceeded their carrying values (as a percent) | 21.50% |  |
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Reporting units exceeded their carrying values (as a percent) | 21.50% |  |

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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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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost 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. 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 325 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75025870&loc=d3e40691-111596 + 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 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 Reference 3: 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 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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