Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Available-for-sale Debt Securities, Amortized Cost Basis	$ 372,182	$ 350,063
Available-for-sale Equity Securities, Amortized Cost Basis	23,393	22,278
Cost Method Investments, Original Cost	$ 4,315	$ 2,749
Preferred Stock, par value	$ 0.0001	$ 0.0001
Preferred stock, authorized shares	1,000,000us-gaap_PreferredStockSharesAuthorized	1,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, issued shares	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, outstanding shares	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized shares	50,000,000us-gaap_CommonStockSharesAuthorized	50,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued shares	21,682,454us-gaap_CommonStockSharesIssued	21,116,497us-gaap_CommonStockSharesIssued
Common stock, outstanding shares	21,470,371us-gaap_CommonStockSharesOutstanding	20,904,414us-gaap_CommonStockSharesOutstanding
Treasury stock	212,083us-gaap_TreasuryStockShares	212,083us-gaap_TreasuryStockShares

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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