Fair Value (Narrative) (Details) (USD $)	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Long-term investments	$ 19,000,000
Maturity term	10 years
Unrealized losses still held	3,246,000	3,099,000
Fair value of auction rate securities	15,700,000
Unrealized gains on long-term Investments	$ 100,000	$ 800,000
Minimum [Member]
Interest rates reset period	7 days
Maximum [Member]
Interest rates reset period	35 days

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