Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Condensed Consolidated Balance Sheet Parenthetical [Abstract]
Allowance for Doubtful Accounts Receivable, Current	$ 99	$ 119
Unamortized debt issuance costs	7	7
Unamortized debt issuance costs, noncurrent	$ 7	$ 14
Common stock, par value	$ 0	$ 0
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	29,545,000	30,305,000
Common stock, shares outstanding	29,545,000	30,305,000

Condensed Consolidated Balance Sheet Parenthetical [Abstract]

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- Definition

Unamortized Debt Issuance Expense, Noncurrent

+ References

No definition available.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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