Financial Instruments And Marketable Securities (Marketable Securities Treated As Available-For-Sale Securities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities, Amortized cost	$ 197	$ 27,048
Total available-for-sale securities, Gross unrealized gains	157	123
Total available-for-sale securities, Gross unrealized losses	0	(6)
Total available-for-sale securities, Fair value	354	27,165
Common Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities, Amortized cost	197	197
Total available-for-sale securities, Gross unrealized gains	157	123
Total available-for-sale securities, Gross unrealized losses	0	0
Total available-for-sale securities, Fair value	354	320
Government And Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Total available-for-sale securities, Amortized cost		26,851
Total available-for-sale securities, Gross unrealized gains		0
Total available-for-sale securities, Gross unrealized losses		(6)
Total available-for-sale securities, Fair value		$ 26,845

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.

+ References+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details