Fair Value Measurements (Details) (USD $)	1 Months Ended	12 Months Ended
	Feb. 29, 2008	Jun. 30, 2010	Sep. 30, 2011		Jun. 30, 2011
Fair Value Measurements [Abstract]
Cash excluded from fair value measurement			$ 156,800,000		$ 165,900,000
Time deposits excluded from fair value measurement			45,117,000	[1]	65,402,000	[1]
Auction Rate Securities, Contractual Maturity Date Range, Low		20
Auction Rate Securities, Contractual Maturity Date Range, High		30
Auction Failure	48,200,000
Available-for-sale Securities, Sold at Par		16,800,000
Total
Fair Value Measurements
Marketable securities			1,898,230,000	[2]	1,807,277,000	[3]
Derivative assets			845,000		1,970,000
Executive Deferred Savings Plan
EDSP money market and other			4,967,000		1,806,000
EDSP mutual funds			110,923,000		126,227,000
Executive Deferred Savings Plan			115,890,000		128,033,000
Total Financial Assets			2,014,965,000	[2]	1,937,280,000	[3]
Derivative liabilities			(6,054,000)		(2,127,000)
Total Financial Liabilities			(6,054,000)		(2,127,000)
Total | Money market and other
Fair Value Measurements
Cash Equivalents			578,442,000		481,770,000
Total | US Treasury securities
Fair Value Measurements
Cash Equivalents					4,400,000
Marketable securities			71,186,000		54,496,000
Total | US Government agency securities
Fair Value Measurements
Cash Equivalents					6,010,000
Marketable securities			344,132,000		314,173,000
Total | Municipal securities
Fair Value Measurements
Marketable securities			40,338,000		38,957,000
Total | Corporate debt securities
Fair Value Measurements
Cash Equivalents					21,982,000
Marketable securities			831,721,000		853,403,000
Total | Sovereign securities
Fair Value Measurements
Marketable securities			32,411,000		32,086,000
Level 1
Fair Value Measurements
Marketable securities			999,948,000	[2]	869,045,000	[3]
Derivative assets			0		0
Executive Deferred Savings Plan
EDSP money market and other			4,967,000		1,806,000
EDSP mutual funds			85,709,000		95,971,000
Executive Deferred Savings Plan			90,676,000		97,777,000
Total Financial Assets			1,090,624,000	[2]	966,822,000	[3]
Derivative liabilities			0		0
Total Financial Liabilities			0		0
Level 1 | Money market and other
Fair Value Measurements
Cash Equivalents			578,442,000		481,770,000
Level 1 | US Treasury securities
Fair Value Measurements
Cash Equivalents					0
Marketable securities			65,387,000		52,396,000
Level 1 | US Government agency securities
Fair Value Measurements
Cash Equivalents					6,010,000
Marketable securities			342,734,000		314,173,000
Level 1 | Municipal securities
Fair Value Measurements
Marketable securities			0		0
Level 1 | Corporate debt securities
Fair Value Measurements
Cash Equivalents					0
Marketable securities			0		0
Level 1 | Sovereign securities
Fair Value Measurements
Marketable securities			13,385,000		14,696,000
Level 2
Fair Value Measurements
Marketable securities			898,282,000	[2]	938,232,000	[3]
Derivative assets			845,000		1,970,000
Executive Deferred Savings Plan
EDSP money market and other			0		0
EDSP mutual funds			25,214,000		30,256,000
Executive Deferred Savings Plan			25,214,000		30,256,000
Total Financial Assets			924,341,000	[2]	970,458,000	[3]
Derivative liabilities			(6,054,000)		(2,127,000)
Total Financial Liabilities			(6,054,000)		(2,127,000)
Level 2 | Money market and other
Fair Value Measurements
Cash Equivalents			0		0
Level 2 | US Treasury securities
Fair Value Measurements
Cash Equivalents					4,400,000
Marketable securities			5,799,000		2,100,000
Level 2 | US Government agency securities
Fair Value Measurements
Cash Equivalents					0
Marketable securities			1,398,000		0
Level 2 | Municipal securities
Fair Value Measurements
Marketable securities			40,338,000		38,957,000
Level 2 | Corporate debt securities
Fair Value Measurements
Cash Equivalents					21,982,000
Marketable securities			831,721,000		853,403,000
Level 2 | Sovereign securities
Fair Value Measurements
Marketable securities			$ 19,026,000		$ 17,390,000

[1] Time deposits excluded from fair value measurements.

[2] Excludes cash of $156.8 million held in operating accounts and time deposits of $45.1 million as of September 30, 2011.

[3] Excludes cash of $165.9 million held in operating accounts and time deposits of $65.4 million as of June 30, 2011.