XML 133 R107.htm IDEA: XBRL DOCUMENT v2.4.0.8

Segment Reporting - Summary of Revenue Attributable to Services Provided by Company (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended												12 Months Ended
	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Segment Reporting Information [Line Items]
Revenues	$ 118,927	$ 117,852	$ 132,296	$ 128,558	$ 108,694	$ 112,167	$ 116,836	$ 117,638	$ 106,375	$ 111,520	$ 125,989	$ 124,066	$ 497,633	$ 455,335	$ 467,950
Revenues percentage													5.00%	5.00%
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues													497,633	455,335	467,950
Revenues percentage													100.00%	100.00%	100.00%
Operating Segments [Member] | Solid Waste Operations [Member]
Segment Reporting Information [Line Items]
Revenues													372,583	342,277	346,582
Revenues percentage													74.90%	75.10%	74.10%
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Collection [Member]
Segment Reporting Information [Line Items]
Revenues													225,441	208,973	205,296
Revenues percentage													45.30%	45.90%	43.90%
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Disposal [Member]
Segment Reporting Information [Line Items]
Revenues													128,778	115,049	123,620
Revenues percentage													25.90%	25.30%	26.40%
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Power Generation [Member]
Segment Reporting Information [Line Items]
Revenues													9,512	11,354	11,894
Revenues percentage													1.90%	2.40%	2.60%
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Processing [Member]
Segment Reporting Information [Line Items]
Revenues													8,852	6,901	5,772
Revenues percentage													1.80%	1.50%	1.20%
Operating Segments [Member] | Organics [Member]
Segment Reporting Information [Line Items]
Revenues													37,829	35,330	30,871
Revenues percentage													7.60%	7.80%	6.60%
Operating Segments [Member] | Customer Solutions [Member]
Segment Reporting Information [Line Items]
Revenues													43,396	35,455	38,302
Revenues percentage													8.70%	7.80%	8.20%
Operating Segments [Member] | Recycling [Member]
Segment Reporting Information [Line Items]
Revenues													$ 43,825	$ 42,273	$ 52,195
Revenues percentage													8.80%	9.30%	11.10%

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13537-108611



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13531-108611



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

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X

- Definition

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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