Fair Value Measurements (Marketable Debt Securities) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	$ 11,808	$ 11,758
Gross Unrealized Gains	49	48
Gross Unrealized Losses	(2)	(7)
Estimated Fair Value	11,855	11,799
Other-than-temporary Impairments	0us-gaap_ImpairmentOfInvestments	0us-gaap_ImpairmentOfInvestments
Municipal bonds - available for sale [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Amortized Cost	11,808	11,758
Gross Unrealized Gains	49	48
Gross Unrealized Losses	(2)	(7)
Estimated Fair Value	11,855	11,799
Other-than-temporary Impairments	$ 0	$ 0

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

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

+ References

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-Publisher FASB

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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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Amount of debt securities categorized neither as held-to-maturity nor trading.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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