Marketable Securities (Schedule Of Marketable Securities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012
Marketable Securities [Line Items]
Cost	$ 29,993
Gross Unrealized Losses	(9)
Fair Value	29,984
Certificates Of Deposit [Member]
Marketable Securities [Line Items]
Cost	15,000
Gross Unrealized Losses	(5)
Fair Value	14,995
Treasury Bills [Member]
Marketable Securities [Line Items]
Cost	14,993
Gross Unrealized Losses	(4)
Fair Value	$ 14,989

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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