XML 132 R117.htm IDEA: XBRL DOCUMENT
v3.20.4

Schedule - Valuation and Qualifying Accounts (Parenthetical) (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract] |  |  |
Valuation allowances on deferred tax assets written off against the deferred tax assets | $ 2,283 | $ 7,588 |
Accounts receivable allowances written off against related accounts receivables | 4,969 | $ 3,539 | $ 6,659
Accounts receivable allowances were netted against deferred revenue | $ 7,089 |  |

X
- Definition Amount of netted accounts receivable charged against deferred revenue. + References No definition available. + Details
Name: | dox_AccountsReceivablesAllowances
Namespace Prefix: | dox_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Valuation of write-downs of deferred tax assets charged against the allowance. + References No definition available. + Details
Name: | dox_DeferredTaxAssetsValuationAllowanceWrittenOff
Namespace Prefix: | dox_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition Amount of direct write-downs of accounts receivable charged against the allowance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration