INCOME TAXES (Effective Income Tax Rate Reconciliation and Income Tax Contingencies) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of effective income tax rate and amount computed using expected U.S. statutory federal rate
Income tax expense at federal statutory rate	$ 1,046,307	$ 803,788	$ 616,654
Adjustment due to:
Foreign rate differential	(289,692)	(226,894)	(175,932)
Innovation Box Tax benefit	(233,545)	(177,195)	(118,916)
Other	44,625	4,040	16,026
Income tax expense	567,695us-gaap_IncomeTaxExpenseBenefit	403,739us-gaap_IncomeTaxExpenseBenefit	337,832us-gaap_IncomeTaxExpenseBenefit
Unrecognized tax benefits
Unrecognized tax benefit — January 1	22,104us-gaap_UnrecognizedTaxBenefits	7,343us-gaap_UnrecognizedTaxBenefits	3,192us-gaap_UnrecognizedTaxBenefits
Gross increases — tax positions in current period	9,305	8,597	4,423
Gross increases — tax positions in prior periods	6,569	3,507	343
Increase acquired in business combination	17,767	7,089	0
Gross decreases — tax positions in prior periods	(2,164)	(495)	(615)
Reduction due to lapse in statute of limitations	(346)	(3,937)	0
Reduction due to settlements during the current period	(879)	0	0
Unrecognized tax benefit — December 31	$ 52,356us-gaap_UnrecognizedTaxBenefits	$ 22,104us-gaap_UnrecognizedTaxBenefits	$ 7,343us-gaap_UnrecognizedTaxBenefits

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Income Tax Reconciliation, Innovation Box Tax Benefit

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit).

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Amount of increase in unrecognized tax benefits resulting from acquisitions.

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