Cash and Cash Equivalents and Short-term Investments (Tables)

12 Months Ended

Dec. 31, 2014

Cash and Cash Equivalents and Short-term Investments

Cash and cash equivalents and short-term investments

	As of December 31,
	2014		2013
	(In thousands)
Cash and cash equivalents	$	501,149	$	389,915
Short-term investments:
Available-for-sale equity securities	$	35,002	$	96,942
Available-for-sale debt securities		18		20,276
Total short-term investments	$	35,020	$	117,218

Certain information related to our cash and cash equivalents and short term investments

	As of December 31,
	2014							2013
	Fair Value		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses
	(In thousands)
Cash and cash equivalents	$	501,149	$	—	$	—		$	389,915	$	—	$	—
Short-term investments:
Available-for-sale equity securities		35,002		14,648		—			96,942		68,395		—
Available-for-sale debt securities:
Corporate debt securities		—		—		—			19,388		4,122		—
Mortgage-backed debt securities		—		—		—			210		11		—
Mortgage-CMO debt securities		18		—		(1	)		20		—		(2	)
Asset-backed debt securities		—		—		—			658		2		(54	)
Total available-for-sale debt securities		18		—		(1	)		20,276		4,135		(56	)
Total available-for-sale securities		35,020		14,648		(1	)		117,218		72,530		(56	)
Total short-term investments		35,020		14,648		(1	)		117,218		72,530		(56	)
Total cash, cash equivalents and
short-term investments	$	536,169	$	14,648	$	(1	)	$	507,133	$	72,530	$	(56	)

Gross unrealized losses of cash and cash equivalents and short-term investments

	As of December 31, 2014
	Less Than 12 Months				More Than 12 Months
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
	(In thousands)
Available-for-sale equity securities	$	—	$	—	$	—	$	—
Available-for-sale debt securities:
Mortgage-CMO debt securities		—		—		18		1
Total available-for-sale debt securities		—		—		18		1
Total	$	—	$	—	$	18	$	1

Estimated fair values of corporate, mortgage-backed, mortgage-CMO and asset-backed debt securities

	Estimated Fair Value As of December 31, 2014
	(In thousands)
Debt securities:
Due in one year or less	$	—
Due after one year through five years		—
Due in more than five years		18
Total debt securities	$	18

Debt and equity securities

	Year Ended December 31,
	2014		2013		2012
	(In thousands)
Available-for-sale
Proceeds from sales and maturities	$	22,313	$	107,586	$	24,010
Realized gains (losses), net	$	4,638	$	88,158	$	13,405