Marketable Investments (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
As reported on the consolidated balance sheets:
Current marketable investments	$ 409,645	$ 325,175
Noncurrent marketable investments	447,749	305,253
Total marketable investments	$ 857,394	$ 630,428

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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