Investments and Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2014

Fair Value Disclosures [Abstract]

Company's recurring financial assets and liabilities subject to fair value measurements

The Company's recurring financial assets and liabilities subject to fair value measurements are as follows:

	Fair Value Measurements as of June 30, 2014
Description	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Money market funds	$	335,332	$	335,332	$	—	$	—
Certificates of deposit	3,252		—		3,252		—
Bonds	5,093		5,093		—		—
Investment securities available for sale							—
Equity securities	123,034		122,262		772		—
Mutual funds invested in fixed income securities	60,522		60,522		—		—
Fixed income securities
U.S. Government securities	11,197		—		11,197		—
Corporate securities	30,648		6,744		23,904		—
U.S. mortgage backed securities	214		—		214		—
Commercial mortgage-backed securities	6,645		—		6,645		—
U.S. asset backed securities	5,061		—		5,061		—
U.S. Government agencies	191		—		191		—
Index-linked U.S. bonds	255		—		255		—
Total fixed income securities	54,211		6,744		47,467		—
Warrants (1)	1,647		—		—		1,647
Total	$	583,091	$	529,953	$	51,491	$	1,647
Liabilities:
Fair value of derivatives embedded within convertible debt	$	191,554	$	—	$	—	$	191,554

(1) Warrants include 1,000,000 of LTS Warrants received on November 4, 2011 which were carried at $1,647 as of June 30, 2014 and are included in "Other assets". The Company recognized a loss of $111 for the six months ended June 30, 2014 related to the change in fair value of the Warrants.

	Fair Value Measurements as of December 31, 2013
Description	Total		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Money market funds	$	130,733	$	130,733	$	—	$	—
Certificates of deposit	2,961		—		2,961		—
Bonds	5,337		5,337		—		—
Investment securities available for sale							—
Equity securities	118,474		117,737		737		—
Fixed income securities							—
U.S. Government securities	13,990		—		13,990		—
Corporate securities	29,923		6,497		23,426		—
U.S. mortgage backed securities	495		—		495		—
Commercial mortgage-backed securities	6,822		—		6,822		—
U.S. asset backed securities	2,081		—		2,081		—
Index-linked U.S. bonds	749		—		749		—
Total fixed income securities	54,060		6,497		47,563		—
Warrants (1)	1,935		—		—		1,935
Total	$	313,500	$	260,304	$	51,261	$	1,935
Liabilities:
Fair value of derivatives embedded within convertible debt	$	112,062	$	—	$	—	$	112,062

(1) Warrants include 1,000,000 of LTS Warrants received on November 4, 2011 which were carried at $1,758 as of December 31, 2013 and are included in "Other assets". The Company recognized income of $65 for the six months ended June 30, 2013 related to the change in fair value of the Warrants.

Unobservable inputs related to the valuations of the Level 3 assets and liabilities

The unobservable inputs related to the valuations of the Level 3 assets and liabilities are as follows at June 30, 2014:

	Quantitative Information about Level 3 Fair Value Measurements
	Fair Value at
	June 30, 2014		Valuation Technique	Unobservable Input	Range (Actual)
Warrants	$	1,647	Option model	Stock price	$	3.15
				Exercise price	$	1.68
				Term (in years)	2.4
				Volatility	45.83		%
				Dividend rate	—
				Risk-free return	0.70		%
Fair value of derivatives embedded within convertible debt	$	191,554	Discounted cash flow	Assumed annual stock dividend	5		%
				Assumed annual cash dividend	$	1.60
				Stock price	$	20.68
				Convertible trading price	107.19		%
				Volatility	16		%
				Implied credit spread	5.5% - 6.5% (6.0%)

The unobservable inputs related to the valuations of the Level 3 assets and liabilities are as follows at December 31, 2013:

	Quantitative Information about Level 3 Fair Value Measurements
	Fair Value at
	December 31, 2013		Valuation Technique	Unobservable Input	Range (Actual)
Warrants	$	1,935	Option model	Stock price	$	3.13
				Exercise price	$	1.68
				Term (in years)	2.8
				Volatility	53.82		%
				Dividend rate	—
				Risk-free return	0.72		%
Fair value of derivatives embedded within convertible debt	$	112,062	Discounted cash flow	Assumed annual stock dividend	5		%
				Assumed annual cash dividend	$	1.60
				Stock price	$	16.37
				Convertible trading price	118.70		%
				Volatility	18		%
				Implied credit spread	7.5% - 8.5% (8.0%)