Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities
Debt securities, Cost	$ 8,361	$ 8,909
Debt securities, Carrying Value	8,563	9,042
Total, Cost	19,010	23,689
Total, Gross Unrealized Gains	7,876	7,533
Total, Gross Unrealized Losses	(98)	(190)
Total, Carrying Value	26,788	31,032
Available-for-sale Securities, Debt Maturities [Abstract]
Due in one year or less, Amortized Cost	3,775	3,786
Due after one year through five years, Amortized Cost	2,685	3,310
Due after five years, Amortized Cost	1,901	1,813
Due in one year or less, Carrying Value	3,922	3,958
Due after one year through five years, Carrying Value	2,678	3,255
Due after five years, Carrying Value	1,963	1,829
Corporate Bond Securities
Schedule of Available-for-sale Securities
Debt securities, Cost	8,361	8,909
Debt securities, Gross Unrealized Gains	228	198
Debt securities, Gross Unrealized Losses	(26)	(65)
Debt securities, Carrying Value	8,563	9,042
Equity Securities
Schedule of Available-for-sale Securities
Marketable equity securities, Cost	10,649	14,780
Marketable equity securities, Gross Unrealized Gains	7,648	7,335
Marketable equity securities, Gross Unrealized Losses	(72)	(125)
Marketable equity securities, carrying value	$ 18,225	$ 21,990

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.