Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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Fair Value Measurements (Details) CAD in Millions	3 Months Ended
Fair Value Measurements (Details) CAD in Millions	Oct. 31, 2016 USD ($)	Oct. 31, 2015 USD ($)	Oct. 31, 2016 CAD	Jul. 31, 2016 USD ($)	Jul. 31, 2015 USD ($)
Business Combination, Contingent Consideration, Liability	$ 11,400,000	$ 6,900,000		$ 11,100,000	$ 6,900,000
Derivative, Maturity Date	Sep. 01, 2020
Money Market Funds, at Carrying Value	$ 3,001,000
Interest Rate Cash Flow Hedge Liability at Fair Value	1,990,000
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	(300,000)	0
Level 1 [Member]
Business Combination, Contingent Consideration, Liability	0	0		0
Money Market Funds, at Carrying Value	3,001,000
Interest Rate Cash Flow Hedge Liability at Fair Value	0
Level 2 [Member]
Business Combination, Contingent Consideration, Liability	0	0		0
Money Market Funds, at Carrying Value	0
Interest Rate Cash Flow Hedge Liability at Fair Value	1,990,000
Fair Value, Inputs, Level 3 [Member]
Business Combination, Contingent Consideration, Liability	11,400,000	6,900,000		11,100,000
Money Market Funds, at Carrying Value	0
Interest Rate Cash Flow Hedge Liability at Fair Value	0
Commercial Paper [Member]
Cash equivalents measured at fair value	2,401,000	2,401,000		2,401,000
Commercial Paper [Member] \| Level 2 [Member]
Cash equivalents measured at fair value	2,401,000	2,401,000		2,401,000
Certificates of Deposit [Member]
Cash equivalents measured at fair value	2,403,000	2,901,000		2,403,000
Certificates of Deposit [Member] \| Level 2 [Member]
Cash equivalents measured at fair value	2,403,000	$ 2,901,000		$ 2,403,000
Canada, Dollars
Derivative, Notional Amount \| CAD			CAD 125.0
United States of America, Dollars
Derivative, Notional Amount	$ 93,200,000