Investments (Schedule Of Debt Securities By Contractual Maturity Date) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Investments [Abstract]
Due within 1 year	$ 46,681	$ 30,512
Due within more than 1 year but less than 5 years	17,209	38,847
Due within more than 5 years but less than 10 years	0	0
Due 10 years or after	2,633	4,230
Total	$ 66,523	$ 73,589

Amount of debt securities categorized neither as held-to-maturity nor trading.

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