FAIR VALUE MEASUREMENTS (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

Financial instruments carried at fair value

Financial assets and liabilities carried at fair value as of March 31, 2018 are classified in the categories described in the tables below (in thousands):

	Level 1		Level 2		Total
ASSETS:
Cash and restricted cash equivalents:
Money market funds	$	1,930,983	$	—	$	1,930,983
International government securities	—		70,025		70,025
Time deposits	37,141		—		37,141
Short-term investments:
International government securities	—		460,890		460,890
U.S. government securities	—		790,425		790,425
Corporate debt securities	—		2,938,400		2,938,400
U.S government agency securities	—		4,408		4,408
Commercial paper	—		46,581		46,581
Long-term investments:
International government securities	—		788,134		788,134
U.S. government securities	—		543,888		543,888
Corporate debt securities	—		5,680,724		5,680,724
U.S. government agency securities	—		494		494
Ctrip convertible debt securities	—		1,411,013		1,411,013
Ctrip equity securities	1,008,510		—		1,008,510
Derivatives:
Currency exchange derivatives	—		440		440
Total assets at fair value	$	2,976,634	$	12,735,422	$	15,712,056

	Level 1		Level 2		Total
LIABILITIES:
Currency exchange derivatives	$	—	$	1,853	$	1,853

Financial assets and liabilities carried at fair value as of December 31, 2017 are classified in the categories described in the tables below (in thousands):

	Level 1		Level 2		Total
ASSETS:
Cash and restricted cash equivalents:
Money market funds	$	1,895,272	$	—	$	1,895,272
U.S. government securities	—		22,265		22,265
Corporate debt securities	—		6,674		6,674
Commercial paper	—		96,321		96,321
Time deposits	17,896		—		17,896
Short-term investments:
International government securities	—		725,376		725,376
U.S. government securities	—		994,118		994,118
Corporate debt securities	—		3,063,315		3,063,315
U.S. government agency securities	—		4,414		4,414
Commercial paper	—		72,650		72,650
Long-term investments:
International government securities	—		607,910		607,910
U.S. government securities	—		834,276		834,276
Corporate debt securities	—		6,656,424		6,656,424
U.S. government agency securities	—		494		494
Ctrip convertible debt securities	—		1,368,500		1,368,500
Ctrip equity securities	953,996		—		953,996
Derivatives:
Currency exchange derivatives	—		1,767		1,767
Total assets at fair value	$	2,867,164	$	14,454,504	$	17,321,668

	Level 1		Level 2		Total
LIABILITIES:
Currency exchange derivatives	$	—	$	127	$	127