Marketable Investment Securities, Restricted Cash and Cash Equivalents, and Other Investment Securities (Details 6) (Investment Securities, USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Investment Securities
Level 3 Investment Securities
Balance at the beginning of the period	$ 105,217
Net realized and unrealized gains (losses) included in earnings	19,289
Net realized and unrealized gains (losses) included in other comprehensive income (loss)	2,961
Purchases	3,480
Settlements	(1,364)
Balance at the end of the period	$ 129,583

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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