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

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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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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Marketable Securities - Schedule of Marketable Securities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 101,131	$ 15,515	$ 24,979	$ 10,029
Available-for-sale Securities [Abstract]
Unrealized Gains		0
Unrealized Losses		(196)
Cash and cash equivalents and available-for-sale securities, amortized cost		18,923
Cash and cash equivalents and available-for-sale securities		18,727
Domestic debt mutual funds
Available-for-sale Securities [Abstract]
Amortized Cost		5,000
Unrealized Gains		0
Unrealized Losses		(196)
Aggregate Fair Value		4,804
Money market funds
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	97,085	13,923
Cash and cash equivalents, aggregate fair value	97,085	13,923
Marketable Securities \| Domestic debt mutual funds
Available-for-sale Securities [Abstract]
Amortized Cost		5,000
Unrealized Gains		0
Unrealized Losses		(196)
Aggregate Fair Value		4,804
Cash and Cash Equivalents \| Money market funds
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents		13,923
Cash and cash equivalents, aggregate fair value		$ 13,923