Fair Value Measurements - Level 3 Liabilities (Details) - USD ($) |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Apr. 30, 2017 |
Jan. 31, 2017 |
Oct. 31, 2016 |
Jul. 31, 2016 |
Apr. 30, 2016 |
Jan. 31, 2016 |
Oct. 31, 2015 |
Apr. 30, 2017 |
|
| Reconciliation of liability measured and recorded at fair value on a recurring basis using Level 3 | ||||||||
| Beginning balance | $ 1,461,000 | $ 1,487,000 | $ 1,579,000 | $ 1,855,000 | $ 1,918,000 | $ 2,050,000 | $ 2,777,000 | $ 1,579,000 |
| Total net unrealized (gains) losses included in general and administrative expense in earnings | (283,000) | 9,000 | 9,000 | (136,000) | 20,000 | 21,000 | (592,000) | |
| Settlements | (48,000) | (47,000) | (70,000) | (196,000) | (95,000) | (100,000) | (120,000) | |
| Foreign currency translation | 8,000 | 12,000 | (31,000) | 56,000 | 12,000 | (53,000) | (15,000) | |
| Ending balance | 1,138,000 | 1,461,000 | 1,487,000 | 1,579,000 | 1,855,000 | 1,918,000 | 2,050,000 | 1,138,000 |
| Impairment of long-lived assets, including goodwill and intangibles with indefinite lives | 0 | |||||||
| Contingent Consideration | Jet Prep Ltd. | ||||||||
| Reconciliation of liability measured and recorded at fair value on a recurring basis using Level 3 | ||||||||
| Beginning balance | 148,000 | 143,000 | 139,000 | 751,000 | ||||
| Total net unrealized (gains) losses included in general and administrative expense in earnings | (148,000) | 5,000 | 4,000 | (612,000) | ||||
| Ending balance | 148,000 | 143,000 | 139,000 | |||||
| Assumed contingent liability | Jet Prep Ltd. | ||||||||
| Reconciliation of liability measured and recorded at fair value on a recurring basis using Level 3 | ||||||||
| Beginning balance | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 |
| Ending balance | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 | 1,138,000 |
| Contingent guaranteed obligation | Cantel Medical (UK) | ||||||||
| Reconciliation of liability measured and recorded at fair value on a recurring basis using Level 3 | ||||||||
| Beginning balance | 323,000 | 349,000 | 441,000 | 569,000 | 637,000 | 773,000 | 888,000 | $ 441,000 |
| Total net unrealized (gains) losses included in general and administrative expense in earnings | (283,000) | 9,000 | 9,000 | 12,000 | 15,000 | 17,000 | 20,000 | |
| Settlements | (48,000) | (47,000) | (70,000) | (196,000) | (95,000) | (100,000) | (120,000) | |
| Foreign currency translation | $ 8,000 | 12,000 | (31,000) | 56,000 | 12,000 | (53,000) | (15,000) | |
| Ending balance | $ 323,000 | $ 349,000 | $ 441,000 | $ 569,000 | $ 637,000 | $ 773,000 | ||