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Comprehensive Income (Details) (USD $)
In Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
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Jun. 30, 2011
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Jun. 30, 2010
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Jun. 30, 2011
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Jun. 30, 2010
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| comprehensive income [Line Items] | ||||
| Net income | $ 17,156 | $ 34,963 | $ 40,495 | $ 83,790 |
| Unrealized (loss) gain on investments | (79) | 67 | (67) | 40 |
| Total comprehensive income | $ 17,077 | $ 35,030 | $ 40,428 | $ 83,830 |
| X | ||||||||||
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- Definition
comprehensive income [Line Items]
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- Definition
The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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