This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 12

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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 other comprehensive income (a separate component of shareholders' equity).

+ References

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

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The increase (decrease) of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. Such increase (decrease) may be comprised of changes in fair value (gains or losses) whether realized or unrealized that have been included in earnings, changed net asset value, or other comprehensive income (a separate component of shareholders' equity); purchases, sales, issuances, or settlements of assets; and net transfers in to or out of this category within the fair value hierarchy.

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Sales 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.

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Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

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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.

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Fair Value Measurement: (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
Fair Value Measurement: (Details) (USD $) In Thousands	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member]	Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Carrying (Reported) Amount, Fair Value Disclosure [Member]	Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Quoted prices in active markets for identical assets (level 1) Certificates of Deposit [Member]	Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Quoted prices in active markets for identical assets (level 1) Certificates of Deposit [Member]	Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Signifcant other observable inputs (level 2) Nontaxable Municipal Notes [Member]	Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Signifcant other observable inputs (level 2) Nontaxable Municipal Notes [Member]	Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Significant unobservable inputs (level 3)	Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Significant unobservable inputs (level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities					$ 52,153	$ 14,507	$ 5,079	$ 2,820	$ 47,074	$ 11,687	$ 0	$ 0
Level 3 investments	0		0
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Investments, Beginning Balance		750		900
Transfers into Level 3		0		0
Sales		(750)		(900)
Unrealized holdig loss, included in other comprehensive income		0		0
Investments, Ending Balance		$ 0		$ 0