Financial Data By Segment And Geographic Area (Narrative) (Details)	12 Months Ended
Jun. 30, 2012
Financial Data By Segment And Geographic Area [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