Interim Financial Data By Segment (Narrative) (Details)	6 Months Ended
Dec. 31, 2011
Interim Financial Data By Segment [Abstract]
Standard reconciling rate between actual interest income earned and interest credited	4.50%

Standard Reconciling Rate Between Actual Interest Income Earned And Interest Credited

No definition available.

Name:	adp_StandardReconcilingRateBetweenActualInterestIncomeEarnedAndInterestCredited
Namespace Prefix:	adp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration