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Investments (Details 2) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | ||
|---|---|---|---|
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Mar. 31, 2015
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Mar. 31, 2014
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Dec. 31, 2014
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| Trading securities portfolio | |||
| Trading securities portfolio | $ 1,118us-gaap_TradingSecuritiesRestricted | $ 1,038us-gaap_TradingSecuritiesRestricted | |
| Gains | 23us-gaap_TradingSecuritiesRealizedGain | 15us-gaap_TradingSecuritiesRealizedGain | |
| U.S. government security funds | |||
| Trading securities portfolio | |||
| Net Unrealized Losses |
$ 8natr_AvailableForSaleSecuritiesNetUnrealizedLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentDebtSecuritiesMember |
$ 15natr_AvailableForSaleSecuritiesNetUnrealizedLosses / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USGovernmentDebtSecuritiesMember |
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| X | ||||||||||
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- Definition
This item represents the net unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities. No definition available.
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| X | ||||||||||
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- Details
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| X | ||||||||||
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- Definition
This item represents the gain realized during the period from the sale of trading securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
Total of all securities that are purchased with the intent to be sold in the short-term and that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Details
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