Fair Value of Financial Instruments (3) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Fair Value Measurements Using Significant Unobservable Inputs (Level 3) [Rollforward]
Beginning balance	$ 7,994	$ 0
Other-than-temporary impairment	0	0
Transfers in from level 2		7,994
Included in other comprehensive income	0	0
Sales	(7,994)	0
Ending balance	$ 0	$ 7,994

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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+ Details