Condensed Consolidated Balance Sheets - Unaudited (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Liabilities and shareholders’ equity
Investments at fair value	$ 24,155us-gaap_InvestmentsFairValueDisclosure	$ 28,370us-gaap_InvestmentsFairValueDisclosure
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000us-gaap_CommonStockSharesAuthorized	100,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	23,083,000us-gaap_CommonStockSharesIssued	23,083,000us-gaap_CommonStockSharesIssued
Common stock, shares outstanding (in shares)	23,005,000us-gaap_CommonStockSharesOutstanding	23,005,000us-gaap_CommonStockSharesOutstanding
Treasury stock, common shares held (in shares)	78,000us-gaap_TreasuryStockShares	78,000us-gaap_TreasuryStockShares

Face amount or stated value per share of common stock.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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