Investments (Schedule Of Debt Securities By Contractual Maturity Date) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Investments [Abstract]
Due within 1 year	$ 55,668	$ 46,681
Due within more than 1 year but less than 5 years	64,392	17,209
Due within more than 5 years but less than 10 years	0	0
Due 10 years or after	2,507	2,633
Total	$ 122,567	$ 66,523