Investments (Details 2) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
As reported on the consolidated balance sheets:
Current marketable investments	$ 121,974	$ 297,842
Noncurrent marketable investments	38,002	122,658
Total marketable investments	$ 159,976	$ 420,500

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

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle.

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