Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015 investment	Dec. 31, 2014 investment
Schedule of Available-for-sale Securities [Line Items]
Investments with other than temporary impairments (investments)	0
Total number in loss position (investments)	2	2
Less than twelve months - fair values	$ 0	$ 5,928
Less than twelve months - unrealized losses	0	(106)
Twelve months or greater - fair values	8,024	8,024
Twelve months or greater - unrealized losses	(54)	(54)
Total Fair Value	8,024	13,952
Total Unrealized Losses	(54)	(160)
Mutual Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Total number in loss position (investments)	2	2
Less than twelve months - fair values	0	5,928
Less than twelve months - unrealized losses	0	(106)
Twelve months or greater - fair values	8,024	8,024
Twelve months or greater - unrealized losses	(54)	(54)
Total Fair Value	8,024	13,952
Total Unrealized Losses	$ (54)	$ (160)

Available-for-sale Securities, Continuous Unrealized Loss Position, Number of Securities in Loss Position

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Other than Temporary Impairment Losses, Number of Investments

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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