Fair Value Measurements (Tables)

3 Months Ended

12 Months Ended

Sep. 30, 2011

Jun. 30, 2011

Fair Value Measurements [Abstract]

Schedule Of Assets Measured At Fair Value On A Recurring Basis

		Level 1		Level 2		Level 3		Total
U.S Treasury and direct obligations of
U.S. government agencies	$	-	$	6,742.7	$	-	$	6,742.7
Corporate bonds		-		6,567.4		-		6,567.4
Asset-backed securities		-		397.9		-		397.9
Commercial mortgage-backed securities		-		433.5		-		433.5
Municipal bonds		-		516.9		-		516.9
Canadian government obligations and
Canadian government agency obligations		-		1,005.3		-		1,005.3
Other securities		14.0		1,571.4		-		1,585.4
Total available-for-sale securities	$	14.0	$	17,235.1	$	-	$	17,249.1

		Level 1		Level 2		Level 3		Total
U.S Treasury and direct obligations of
U.S. government agencies	$	-	$	6,759.1	$	-	$	6,759.1
Corporate bonds		-		6,126.6		-		6,126.6
Asset-backed securities		-		447.8		-		447.8
Commercial mortgage-backed securities		-		492.5		-		492.5
Municipal bonds		-		516.2		-		516.2
Canadian government obligations and
Canadian government agency obligations		-		1,101.5		-		1,101.5
Other securities		20.1		1,463.7		-		1,483.8
Total available-for-sale securities	$	20.1	$	16,907.4	$	-	$	16,927.5