ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) - USD ($) $ in Millions		Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' equity		$ 6,915	$ 8,785	$ 10,636	$ 11,261
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' equity	[1]	(141)	(129)
Foreign currency translation adjustments | Net Investment Hedging | Euro Senior Notes
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' equity		31	(26)
Stockholders' equity, before tax		56	(20)
Foreign currency translation adjustments | Net Investment Hedging | Foreign Currency Forward
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' equity		(35)	(35)
Stockholders' equity, before tax		(53)	(53)
Net unrealized gains (losses) on marketable securities | Debt Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' equity	[2]	(28)	(187)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' equity		(169)	(316)	$ 58	$ 238
Accumulated Net Investment Gain (Loss) Attributable to Parent | Debt Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent		81	30
Currency translation adjustment on deemed repatriation tax liability [Member] | Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent		$ (52)	$ (41)

[1] Foreign currency translation adjustments, net of tax, at March 31, 2019 and December 31, 2018, include accumulated net losses from fair value adjustments of $35 million after tax ($53 million before tax) associated with previously settled derivatives that were designated as net investment hedges. Foreign currency translation adjustments, net of tax, include foreign currency transaction gains of $31 million after tax ($56 million before tax) and foreign currency transaction losses of $26 million after tax ($20 million before tax) at March 31, 2019 and December 31, 2018, respectively, associated with the Company's Euro-denominated debt. The Company's Euro-denominated debt is designated as a hedge against the impact of currency fluctuations on its Euro-denominated net assets (see Note 9). The remaining balance in foreign currency translation adjustments relates to the cumulative impacts of currency fluctuations on the Company's non-U.S. Dollar denominated net assets. At March 31, 2019 and December 31, 2018, the Company had deferred tax benefits of $52 million and $41 million, respectively, related to foreign currency translation adjustments to its one-time deemed repatriation tax liability recorded at December 31, 2017 and foreign earnings for periods after December 31, 2017 that are subject to U.S. federal and state income tax, resulting from the introduction of the Tax Act.

[2] Net unrealized losses on debt securities, net of tax, includes cumulative tax charges of $81 million and $30 million at March 31, 2019 and December 31, 2018, respectively.