Marketable Investment Securities, Restricted Cash and Other Investment Securities (Details 5) (Investment Securities, USD $) In Thousands | 9 Months Ended |
|---|---|
Sep. 30, 2011 | |
Investment Securities | |
| Level 3 Investment Securities | |
| Balance at the beginning of the period | $ 608,955 |
| Net realized and unrealized gains (losses) included in earnings | 3,507 |
| Purchases | 51,936 |
| Issuances | 27,313 |
| Settlements | 551,865 |
| Balance at the end of the period | $ 139,846 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
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- Definition This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Issues that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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