Financial Instruments And Fair Value Measurements (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Sep. 30, 2012	Jun. 30, 2012
Schedule of Available-for-sale Securities [Line Items]
Cumulative impairment losses recorded in AOCI	$ 4.3
Cumulative impairment losses recorded in AOCI, net of tax	2.7
Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cumulative impairment losses, investments	18.3	18.3
Cumulative other-than-temporary impairment losses, investments	14.0	14.0
Credit based OTTI losses recorded in Statement of Operations	14.0
Auction Rate Securities [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Auction rate securities, interest rate setting interval (in days)	7 days
Auction Rate Securities [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Auction rate securities, interest rate setting interval (in days)	35 days
Student Loans Guaranteed By FFELP [Member] \| Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Auction rate securities, fair value	29.9
Aggregate discount from cost, percentage	8.00%
Student Loans Guaranteed By AMBAC [Member] \| Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Auction rate securities, fair value	$ 4.4
Aggregate discount from cost, percentage	78.00%

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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