Operating Segments - Concentration Risk (Details) - customer
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6 Months Ended |
Jan. 31, 2016 |
Jan. 31, 2015 |
| Concentration risk |
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|
| Number of customers that each account for 10% or more of the consolidated net sales of the company |
0
|
0
|
| Segment sales | Customer concentration | Water Purification and Filtration |
|
|
| Concentration risk |
|
|
| Number of customers accounting for a percentage of segment net sales |
2
|
|
| Segment sales | Customer concentration | Water Purification and Filtration | Two customers |
|
|
| Concentration risk |
|
|
| Concentration risk within segment (as a percent) |
43.20%
|
|
| Segment sales | Customer concentration | Healthcare Disposables | Four customers |
|
|
| Concentration risk |
|
|
| Number of customers accounting for a percentage of segment net sales |
4
|
|
| Concentration risk within segment (as a percent) |
51.00%
|
|
| Net sales | Customer concentration | Dialysis | Two customers |
|
|
| Concentration risk |
|
|
| Number of customers accounting for a percentage of segment net sales |
2
|
|
| Concentration risk within segment (as a percent) |
42.90%
|
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