Segment Reporting - Summary of Financial Information by Reportable Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Inter-company revenues	$ 116,577us-gaap_Revenues	$ 113,197us-gaap_Revenues
Depreciation and amortization	13,748	13,608
Operating income (loss)	3,126us-gaap_OperatingIncomeLoss	(3,674)us-gaap_OperatingIncomeLoss
Total assets	654,404us-gaap_Assets	660,438us-gaap_Assets	669,795us-gaap_Assets
Eastern Region [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	33,267	31,338
Depreciation and amortization	5,237	5,329
Operating income (loss)	(485)	(4,860)
Total assets	205,062	200,137
Western Region [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	49,357	48,739
Depreciation and amortization	6,738	6,524
Operating income (loss)	4,995	2,603
Total assets	325,799	340,862
Recycling [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	10,294	10,361
Depreciation and amortization	1,116	1,066
Operating income (loss)	(2,010)	(1,484)
Total assets	50,157	49,519
Other [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	23,659	22,759
Depreciation and amortization	657	689
Operating income (loss)	626	67
Total assets	73,386	69,920
Intersubsegment Eliminations [Member] \| Inter-Company Revenue [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	(22,639)	(24,413)
Intersubsegment Eliminations [Member] \| Eastern Region [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	8,016	8,588
Intersubsegment Eliminations [Member] \| Western Region [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	14,398	15,384
Intersubsegment Eliminations [Member] \| Recycling [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	4	(63)
Intersubsegment Eliminations [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Inter-company revenues	$ 221	$ 504

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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 210.5-02.18)

-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 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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+ References

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

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