TREASURY STOCK (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Apr. 28, 2016	Feb. 24, 2016	Sep. 11, 2015
TREASURY STOCK PURCHASE
Cash paid for repurchase of common stock	$ 2,016	$ 251,382
Number of shares repurchased of common stock from employees in lieu of cash or withholding taxes due	15,277
Cash payment for repurchase of common stock from employees in lieu of cash or withholding taxes due	$ 2,000
Existing share repurchase program | Subsequent event
TREASURY STOCK PURCHASE
Stock repurchase program, authorized amount				$ 2,000,000
February 2016 Repurchase Plan
TREASURY STOCK PURCHASE
Stock repurchase program, authorized amount					$ 1,750,000
Common stock repurchased (in shares)	0
September 2015 Repurchase Plan
TREASURY STOCK PURCHASE
Stock repurchase program, authorized amount						$ 500,000
Remaining authorized purchase amount	$ 250,000
Common stock repurchased (in shares)	0		1,900,000
Average purchase price (in dollars per share)			$ 134.26
Cash paid for repurchase of common stock			$ 250,000