FAIR VALUE MEASUREMENTS AND FINANCIAL INSTRUMENTS (Details 1) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($) arrangement	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) arrangement	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Auction rate securities
Cost basis	$ 232,766		$ 232,766		$ 159,418
Gross unrealized losses	$ 0		$ 0		255
Contingent Consideration Arrangements
Number of contingent consideration arrangements related to business acquisitions | arrangement	9		9
Number of contingent consideration arrangements with payment limit | arrangement	8		8
Contingent consideration, maximum amount at balance sheet date	$ 240,700		$ 240,700
Contingent consideration, fair value at balance sheet date with a maximum limit	$ 31,400		$ 31,400
Number of contingent consideration arrangements without payment limit | arrangement	1		1
Contingent consideration, fair value at balance sheet date without a limit	$ 500		$ 500
Contingent consideration, at fair value, current	2,800		2,800
Contingent consideration, at fair value, noncurrent	29,100		29,100
Assets measured at fair value on a nonrecurring basis
Cost method investments	103,300		103,300		90,900
Cost method investments, other than temporary impairment		$ 64,200
Equity method investment, other than temporary impairment		4,200
Long-term marketable equity security
Cost basis	97		97		98
Gross unrealized gain	509		509		1,353
Gross unrealized loss	0		0		0
Auction rate security
Changes in assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3)
Balance at the beginning of the period, assets	6,190	9,150	6,070	$ 8,920
Total net gains (losses) included in other comprehensive income (loss), Asset	440	100	560	330
Balance at the end of the period, assets	6,630	9,250	6,630	9,250
Auction rate securities
Cost basis	10,000		10,000		10,000
Gross unrealized losses	3,400		3,400		3,900
Contingent Consideration Arrangement
Changes in liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3)
Balance at the beginning of the period	(20,964)	(48,758)	(30,140)	(45,828)
Total net gains (losses) included in earnings, fair value adjustments	9,950	(527)	16,946	(500)
Total net gains (losses) included in earnings, foreign currency exchange gains	(4)	0	626	0
Total net gains (losses) included in other comprehensive income (loss), Liability	384	499	2,117	136
Fair value at date of acquisition	(26,749)	0	(27,112)	(2,835)
Settlements	5,525	7,389	5,705	7,630
Balance at the end of the period	(31,858)	$ (41,397)	$ (31,858)	$ (41,397)
Contingent Consideration Arrangement | Minimum [Member]
Contingent Consideration Arrangements
Contingent consideration, discount rates			12.00%
Contingent Consideration Arrangement | Maximum [Member]
Contingent Consideration Arrangements
Contingent consideration, discount rates			25.00%
Equity security
Long-term marketable equity security
Cost basis	8,700		$ 8,700		8,700
Gross unrealized gain	$ 2,700		$ 2,700
Gross unrealized loss					$ 1,200