XML 31 R81.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Segment Reporting (Narrative) (Details) | 12 Months Ended
--- | ---
Jul. 31, 2015 segment customer | Jul. 31, 2014 customer | Jul. 31, 2013 customer
Segment Reporting, Measurement Disclosures [Abstract] |  |  |
Number of reportable segments | segment | 2 |  |
Number of customers accounting for over 10% of net sales | 0 | 0 | 0
Number of customers accounting for over 10% of gross accounts receivable | 0 | 0 |

X
- Definition Number Of Customers Accounting For Over Ten Percent Of Gross Accounts Receivable + References No definition available. + Details
Name: | dci_NumberOfCustomersAccountingForOverTenPercentOfGrossAccountsReceivable
Namespace Prefix: | dci_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Customers Accounting For Over Ten Percent Of Net Sales + References No definition available. + Details
Name: | dci_NumberOfCustomersAccountingForOverTenPercentOfNetSales
Namespace Prefix: | dci_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NumberOfReportableSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_SegmentReportingMeasurementDisclosuresAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration