EMPLOYEE BENEFITS - Fair Value of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2016		Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	$ 104		$ 182
Investments measured at net asset value	918	[1]	767
Liabilities measured at fair value			2
Cash and money market funds | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		4
Managed portfolio | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	2		4
Managed portfolio | U.S. government obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	10		35
Managed portfolio | Municipal obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	2		1
Managed portfolio | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	89		84
Managed portfolio | Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	1		5
Managed portfolio | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			1
Managed portfolio | Interest rate forwards
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			1
Liabilities measured at fair value			1
Managed portfolio | Credit default swaps
Defined Benefit Plan Disclosure [Line Items]
Liabilities measured at fair value			1
Mutual funds | International equity funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			47
Level 1
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		47
Liabilities measured at fair value			0
Level 1 | Cash and money market funds | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 1 | Managed portfolio | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 1 | Managed portfolio | U.S. government obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 1 | Managed portfolio | Municipal obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 1 | Managed portfolio | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 1 | Managed portfolio | Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 1 | Managed portfolio | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			0
Level 1 | Managed portfolio | Interest rate forwards
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			0
Liabilities measured at fair value			0
Level 1 | Managed portfolio | Credit default swaps
Defined Benefit Plan Disclosure [Line Items]
Liabilities measured at fair value			0
Level 1 | Mutual funds | International equity funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			47
Level 2
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	104		135
Liabilities measured at fair value			2
Level 2 | Cash and money market funds | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		4
Level 2 | Managed portfolio | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	2		4
Level 2 | Managed portfolio | U.S. government obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	10		35
Level 2 | Managed portfolio | Municipal obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	2		1
Level 2 | Managed portfolio | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	89		84
Level 2 | Managed portfolio | Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	1		5
Level 2 | Managed portfolio | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			1
Level 2 | Managed portfolio | Interest rate forwards
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			1
Liabilities measured at fair value			1
Level 2 | Managed portfolio | Credit default swaps
Defined Benefit Plan Disclosure [Line Items]
Liabilities measured at fair value			1
Level 2 | Mutual funds | International equity funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			0
Level 3
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Liabilities measured at fair value			0
Level 3 | Cash and money market funds | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 3 | Managed portfolio | Cash and money market funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 3 | Managed portfolio | U.S. government obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 3 | Managed portfolio | Municipal obligations
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 3 | Managed portfolio | Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 3 | Managed portfolio | Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	0		0
Level 3 | Managed portfolio | Mortgage-backed securities
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			0
Level 3 | Managed portfolio | Interest rate forwards
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			0
Liabilities measured at fair value			0
Level 3 | Managed portfolio | Credit default swaps
Defined Benefit Plan Disclosure [Line Items]
Liabilities measured at fair value			0
Level 3 | Mutual funds | International equity funds
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value			0
Investments
Defined Benefit Plan Disclosure [Line Items]
Assets at fair value	$ 1,022		$ 949

[1] Certain investments that were measured at net asset value per share (or its equivalent) have not been classified in the fair value hierarchy.