CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Unrealized gain from derivatives, income tax benefit		$ 161
Net change in unrealized gains and losses on marketable securities, income tax benefit	$ 2,380	$ 6,793

Other Comprehensive Income Net Unrealized Gains Losses On Marketable Securities Net Of Tax, Tax Amount

No definition available.

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