Retirement Benefits (Details4)	12 Months Ended
	Jun. 30, 2012
Investment Policies And Strategies [Abstract]
Investment Policies and Strategies Narrative Description	We monitor investment performance and portfolio characteristics on a quarterly basis to ensure that managers are meeting expectations with respect to their investment approach. With the exception of securities issued by the U.S. Government and its agencies, no single issue is to comprise more than 5% of the portfolio’s value although index fund managers are exempt from the security weighting constraints. There are also various restrictions and controls placed on managers, including prohibition from investing in our stock. Our investment strategy is designed to generate returns that will reduce the interest rate risk inherent in each of the plans’ benefit obligations and enable the plans to meet their future obligations. The precise amount for which these obligations will be settled depends on future events, including the life expectancy of the plan’s members and salary inflation. The obligations are estimated using actuarial assumptions, based on the current economic environment. Each pension plan seeks to achieve total returns sufficient to meet expected future obligations when considered in conjunction with expected future company contributions and prudent levels of investment risk and diversification. Each plan’s targeted asset allocation is determined through a plan-specific Asset-Liability Modeling study. These comprehensive studies provide an evaluation of the projected status of asset and benefit obligation measures for each plan under a range of both positive and negative environments. The studies include a number of different asset mixes, spanning a range of diversification and potential equity exposures. In evaluating the strategic asset allocation choices, an emphasis is placed on the long-term characteristics of each individual asset class, such expected return, volatility of returns and correlations with other asset classes within the portfolios. Consideration is also given to the proper long-term level of risk for each plan, the impact on the volatility and magnitude of plan contributions and cost, and the impact certain actuarial techniques may have on the plan's recognition of investment experience.
US funded pension plan
Investment Policies And Strategies [Abstract]
Target Allocation Percentage	0.67
Legacy Watson Wyatt Canadian funded pension plan
Investment Policies And Strategies [Abstract]
Target Allocation Percentage	0.65
Legacy Watson Wyatt UK funded pension plan
Investment Policies And Strategies [Abstract]
Target Allocation Percentage	0.40
Legacy Towers Perrin Canadian funded pension plan
Investment Policies And Strategies [Abstract]
Target Allocation Percentage	0.50
Legacy Towers Perrin UK funded pension plan
Investment Policies And Strategies [Abstract]
Target Allocation Percentage	0.40
Netherlands funded pension plan
Investment Policies And Strategies [Abstract]
Target Allocation Percentage	The Netherlands plan is invested in an insurance contract. Consequently, the asset allocation of the plan is managed by the insurer.