Acquisitions (Details 5) (USD $)	0 Months Ended	3 Months Ended								12 Months Ended							0 Months Ended	1 Months Ended	12 Months Ended			24 Months Ended			12 Months Ended		0 Months Ended
	Jul. 12, 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, 2013	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2013 Endoscopy	Jul. 31, 2012 Endoscopy	Jul. 31, 2011 Endoscopy	Aug. 02, 2011 Second Amended and Restated Credit Agreement	Aug. 02, 2011 BMI Medivators subsidiary item	Dec. 31, 2011 BMI Medivators subsidiary	Jul. 31, 2013 BMI Medivators subsidiary	Jul. 31, 2012 BMI Medivators subsidiary	Dec. 31, 2010 BMI Medivators subsidiary	Jul. 31, 2012 BMI Medivators subsidiary	Jan. 31, 2013 BMI Medivators subsidiary	Jul. 29, 2011 BMI Medivators subsidiary	Jul. 31, 2012 BMI Medivators subsidiary General administrative expenses	Jul. 31, 2011 BMI Medivators subsidiary General administrative expenses	Aug. 02, 2011 BMI Medivators subsidiary Customer relationships	Aug. 02, 2011 BMI Medivators subsidiary Brand name	Aug. 02, 2011 BMI Medivators subsidiary Technology	Aug. 02, 2011 BMI Medivators subsidiary Non-compete agreement	Aug. 02, 2011 BMI Medivators subsidiary Minimum	Aug. 02, 2011 BMI Medivators subsidiary Maximum	Aug. 02, 2011 BMI Medivators subsidiary Purchase of land and buildings from Byrne Investments LLC
Acquisitions
Estimated acquisition-related costs																						$ 1,099,000			$ 626,000	$ 473,000
Aggregate purchase price																		99,361,000
Reduction in goodwill resulting from net asset value adjustment																		639,000
Portion of purchase price paid in cash																		89,361,000
Portion of purchase price paid in shares																	10,000,000
Price floor period																	3 years
Stock split ratio	1.5																1.5
Stock consideration (in shares)																	902,528
Closing share price of Cantel to determine stock consideration (in dollars per share)																								$ 11.08
Potential cash contingent consideration payable																	10,000,000
Period over which potential cash contingent consideration is payable																	2 years
Purchase price																																	5,900,000
Change in fair value of contingent consideration liability																			1,500,000	1,200,000
Contingent consideration																							0
Aggregate value of the stock consideration threshold																	10,000,000
Change in fair value of price floor liability																			992,000	1,963,000
Price floor liability																			45,000
Lock-up period prohibiting sellers from trading Cantel common stock																															3 years	4 years
Fair value of shares																	7,640,000
Portion of fair value of shares determined as stock-based compensation expense																	330,000
Components of the purchase price
Cash (including purchase of buildings)																	95,261,000
Fair value of the multi-year lock-up of Cantel common stock																	7,310,000
Consideration for the transaction																	102,571,000
Price floor																	3,000,000
Contingent consideration																	2,700,000
Total purchase price recorded																	108,271,000
Credit facility entered in conjunction with the acquisition and impending expiration of existing credit facility																150,000,000
Net Assets
Accounts receivable																	4,303,000
Inventory																	4,581,000
Other assets																	588,000
Property, plant and equipment																	10,074,000
Amortizable intangible assets																											25,300,000	2,200,000	11,900,000	2,000,000
Other assets, Noncurrent																	105,000
Current liabilities																	(2,277,000)
Other liabilities																	(85,000)
Net assets acquired																	58,689,000
Amortizable intangible assets, useful life																	13 years										15 years	10 years	8 years	14 years
Number of in-process research and development projects acquired																	0
Goodwill deductible for income tax purposes																	49,582,000
Period for income tax deduction																	15 years
Revenues generated by acquiree in latest fiscal year before the business acquisition																					34,293,000
Gross profit generated by acquiree in latest audited fiscal year before the business acquisition																					21,991,000
Condensed Consolidated Financial Statements:
Net sales		$ 113,973,000	$ 105,009,000	$ 106,363,000	$ 99,681,000	$ 98,693,000	$ 97,238,000	$ 97,297,000	$ 93,262,000	$ 425,026,000	$ 386,490,000	$ 321,651,000	$ 160,317,000	$ 153,224,000	$ 102,484,000