INVESTMENTS

The following table summarizes, by major security type, the Company's investments as of June 30, 2015 (in thousands):



	Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Available-for-sale securities:
Short-term investments:
Foreign government securities	$	199,505	$	11	$	(55	)	$	199,461
U.S. government securities	587,802		75		(14		)	587,863
Corporate debt securities	512,054		63		(314		)	511,803
Total short-term investments	$	1,299,361	$	149	$	(383	)	$	1,299,127

Long-term investments:
Foreign government securities	$	428,402	$	69	$	(960	)	$	427,511
U.S. government securities	733,461		2,108		(409		)	735,160
Corporate debt securities	3,937,924		4,295		(8,167		)	3,934,052
U.S. government agency securities	2,015		3		—			2,018
U.S. municipal securities	1,097		7		—			1,104
Ctrip convertible debt securities	750,000		10,399		—			760,399
Ctrip equity securities	421,930		113,294		—			535,224
Total long-term investments	$	6,274,829	$	130,175	$	(9,536	)	$	6,395,468

The Company's investment policy seeks to preserve capital and maintain sufficient liquidity to meet operational and other needs of the business. As of June 30, 2015, the weighted-average life of the Company’s U.S. Dollar and Euro fixed income investment portfolios, excluding the Company's investment in Ctrip convertible debt securities, was approximately 1.8 years with an average credit quality of A1/A+.

The Company invests in foreign government securities with high credit quality. As of June 30, 2015, investments in foreign government securities principally included debt securities issued by the governments of the Netherlands, France, Belgium, Austria and the United Kingdom.

On May 26, 2015 and August 7, 2014, the Company invested $250 million and $500 million, respectively, in five-year senior convertible notes issued at par by Ctrip.com International Ltd. ("Ctrip"). Additionally, as of June 30, 2015, the Company had invested $421.9 million of its international cash in Ctrip American Depositary Shares ("ADSs"). The convertible debt and equity securities of Ctrip have been marked to market in accordance with the accounting guidance for available-for-sale securities and at June 30, 2015 show unrealized gains of $10.4 million and $113.3 million, respectively. In connection with the purchase of the convertible note in August 2014, Ctrip granted the Company the right to appoint an observer to Ctrip's board of directors and permission to acquire Ctrip shares (through the acquisition of Ctrip ADSs in the open market) over the twelve months following the purchase date, so that combined with ADSs issuable upon conversion of this note, the Company could hold up to 10% of Ctrip's outstanding equity. In connection with the purchase of the convertible note in May 2015, Ctrip granted the Company permission to acquire additional Ctrip shares (through the acquisition of Ctrip ADSs in the open market) over the twelve months following the purchase date, so that combined with ADSs issuable upon conversion of the two notes, the Company could hold up to an aggregate of 15% of Ctrip's outstanding equity.

The following table summarizes, by major security type, the Company's investments as of December 31, 2014 (in thousands):



	Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Available-for-sale securities:
Short-term investments:
Foreign government securities	$	52,524	$	—	$	(34	)	$	52,490
U.S. government securities	364,276		24		(34		)	364,266
Corporate debt securities	582,160		15		(652		)	581,523
Commercial paper	39,092		—		—			39,092
U.S. government agency securities	104,829		—		(18		)	104,811
Total short-term investments	$	1,142,881	$	39	$	(738	)	$	1,142,182

Long-term investments:
Foreign government securities	$	12,707	$	—	$	(36	)	$	12,671
U.S. government securities	557,130		80		(762		)	556,448
Corporate debt securities	2,332,030		2,299		(5,296		)	2,329,033
U.S. government agency securities	95,108		97		(111		)	95,094
U.S. municipal securities	1,114		—		(12		)	1,102
Ctrip convertible debt securities	500,000		—		(74,039		)	425,961
Ctrip equity securities	421,930		—		(86,586		)	335,344
Total long-term investments	$	3,920,019	$	2,476	$	(166,842	)	$	3,755,653

The Company has classified its investments as available-for-sale securities. These securities are carried at estimated fair value with the aggregate unrealized gains and losses related to these investments, net of taxes, reflected as a part of "Accumulated other comprehensive loss" in the Unaudited Consolidated Balance Sheets. Classification as short term or long term is based upon the maturity of the debt securities.

The Company recognized $1.6 million and $3.4 million of net realized gains related to investments for the three and six months ended June 30, 2015, respectively. There were no realized gains or losses related to investments for the three and six months ended June 30, 2014.