LONG-TERM DEBT - Senior Secured Credit Facilities Narrative (Details) € in Millions														1 Months Ended	3 Months Ended			12 Months Ended
	May 29, 2015	Apr. 01, 2015 USD ($)	Mar. 27, 2015 USD ($)	Mar. 27, 2015 EUR (€)	Jan. 30, 2015 USD ($)	Jan. 22, 2015 USD ($)	Feb. 06, 2014 USD ($)	Dec. 02, 2013 USD ($)	Jul. 12, 2013 USD ($)	Oct. 04, 2012 USD ($)	Mar. 08, 2011 USD ($)	Feb. 08, 2011 USD ($)	Sep. 28, 2010 USD ($)	Jul. 31, 2014 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Feb. 20, 2015 USD ($)
Long-term debt, net of unamortized debt discount [Line Items]
Loss on extinguishment of debt																	$ 94,000,000	$ 0	$ 20,000,000	$ 130,000,000
Periodic principal payment																		2,436,000,000
Unamortized discounts																		323,000,000
Revolving credit facility
Long-term debt, net of unamortized debt discount [Line Items]
Maximum borrowing capacity						$ 1,500,000,000.00
Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Periodic principal payment																		1,841,000,000
Repayments of term loans from asset sale proceeds																		140,000,000
Additional voluntary prepayments																		275,000,000
Mandatory excess cash flow payment																		125,000,000
Revolving credit facility																		$ 625,000,000
Series E-1 Tranche B Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed							$ 2,950,000,000
Series E-1 Tranche B Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		3.50%
Series E-1 Tranche B Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		4.50%
Series A-3 Tranche A Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed						$ 250,000,000	$ 226,000,000
Quarterly amortization payment																		$ 99,000,000
Series A-3 Tranche A Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		2.75%
Series A-3 Tranche A Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		3.75%
Secured Debt
Long-term debt, net of unamortized debt discount [Line Items]
Periodic principal payment														$ 1,000,000,000
Incremental Term Loan Facilities
Long-term debt, net of unamortized debt discount [Line Items]
Debt issuance cost		$ 85,000,000
Unamortized discounts		21,000,000
Incremental Term Loan Facilities | Salix
Long-term debt, net of unamortized debt discount [Line Items]
Maximum borrowing capacity		5,150,000,000.00																			$ 5,150,000,000.00
Series A-4 Tranche Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Maximum borrowing capacity		$ 1,000,000,000.00
Quarterly amortization rate, year one		5.00%
Quarterly amortization rate, year two		10.00%
Quarterly amortization rate, year three		20.00%
Series A-4 Tranche Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		2.75%
Series A-4 Tranche Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		3.75%
Series A-4 Tranche Term Loan Facility | Amortization payment period one
Long-term debt, net of unamortized debt discount [Line Items]
Quarterly amortization payment																		$ 48,000,000
Series A-4 Tranche Term Loan Facility | Minimum | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins		0.75%
Series A-4 Tranche Term Loan Facility | Minimum | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins		1.75%
Series A-4 Tranche Term Loan Facility | Maximum | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins		1.25%
Series A-4 Tranche Term Loan Facility | Maximum | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins		2.25%
Series F Tranche B Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Maximum borrowing capacity		$ 4,150,000,000.00
Quarterly amortization rate, year one		1.00%
Quarterly amortization payment																		$ 10,000,000
Series F Tranche B Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		3.75%
Variable rate floor (as a percent)		1.75%																1.75%
Series F Tranche B Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		4.75%
Variable rate floor (as a percent)		0.75%																0.75%
Series F Tranche B Term Loan Facility | Minimum | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins		2.00%
Series F Tranche B Term Loan Facility | Minimum | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins		3.00%
Series F Tranche B Term Loan Facility | Maximum | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins		2.25%
Series F Tranche B Term Loan Facility | Maximum | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins		3.25%
Series D-2 Tranche B Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins	1.75%
Variable rate floor (as a percent)	1.75%
Series D-2 Tranche B Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins	2.75%
Variable rate floor (as a percent)	0.75%
Series D-2 Tranche B Term Loan Facility | Minimum | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Basis spread in future periods	1.75%
Series D-2 Tranche B Term Loan Facility | Minimum | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Basis spread in future periods	2.75%
Series D-2 Tranche B Term Loan Facility | Maximum | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Basis spread in future periods	1.50%
Series D-2 Tranche B Term Loan Facility | Maximum | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Basis spread in future periods	2.50%
Amortization payment period one | Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Aggregate principal reduction																		$ 556,000,000
Series A1 and A2 Tranche A Term Loan Facilities | Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Periodic principal payment																		260,000,000
Amortization payment period two | Term Loan Facility
Long-term debt, net of unamortized debt discount [Line Items]
Aggregate principal reduction																		$ 610,000,000
Series A-2 Tranche A Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		2.75%
Series A-2 Tranche A Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		3.75%
Series A-1 Tranche A Term Loan Facility | Base Rate
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		2.75%
Series A-1 Tranche A Term Loan Facility | LIBOR
Long-term debt, net of unamortized debt discount [Line Items]
Margins																		3.75%
Senior Secured Credit Facilities
Long-term debt, net of unamortized debt discount [Line Items]
Percentage of net cash proceeds of insurance and condemnation proceeds for property or asset losses																		100.00%
Percentage of cash proceeds from issuance of equity securities payable as mandatory prepayments																		50.00%
Percentage of cash proceeds from incurrence of debt																		100.00%
Percentage of annual excess cash flow																		50.00%
Percentage of cash proceeds from asset sales outside the ordinary course of business payable as mandatory prepayments																		100.00%
Percentage of capital stock of the entity and domestic subsidiaries pledged as collateral for borrowings																		100.00%
Percentage of capital stock of foreign subsidiaries pledged as collateral for borrowings																		65.00%
Senior Secured Credit Facilities | Revolving credit facility
Long-term debt, net of unamortized debt discount [Line Items]
Commitment fee, unutilized commitments, percentage																		0.50%
6.875% Senior Notes due in December 2018
Long-term debt, net of unamortized debt discount [Line Items]
Loss on extinguishment of debt															$ 20,000,000	$ 18,000,000
7.00% Senior Notes due in October 2020
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed													$ 700,000,000
6.75% Senior Notes due in August 2021
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed												$ 650,000,000
7.25% Senior Notes due in July 2022
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed											$ 550,000,000
6.375% Senior Notes due in October 2020
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed										$ 1,750,000,000
6.75% Senior Notes due August 2018
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed									$ 1,600,000,000
7.50% Senior Notes due July 2021
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed									$ 1,625,000,000
5.625 % Senior Notes due December 2021
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed								$ 900,000,000
5.50% Senior Notes due March 2023
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed					$ 1,000,000,000
5.375% Senior Notes due March 2020
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed			$ 2,000,000,000
5.875% Senior Notes due May 2023
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed			3,250,000,000
4.50% Senior Notes Due 2023
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed | €				€ 1,500
6.125% Senior Notes due April 2025
Long-term debt, net of unamortized debt discount [Line Items]
Amount borrowed			$ 3,250,000,000