Statements Of Consolidated Earnings (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Direct pass-through costs, Professional Employer Organization revenues	$ 7,018.9adp_DirectPassThroughCostsPEORevenues	$ 6,396.8adp_DirectPassThroughCostsPEORevenues	$ 19,972.5adp_DirectPassThroughCostsPEORevenues	$ 17,484.4adp_DirectPassThroughCostsPEORevenues

Direct pass-through costs associated with PEO, primarily consisting of payroll wages and payroll taxes.

No definition available.

Name:	adp_DirectPassThroughCostsPEORevenues
Namespace Prefix:	adp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration