DEBT AND CREDIT FACILITIES DEBT AND CREDIT FACILITIES (Schedule of Extinguishment of Debt) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
$400 Million 5.90% 2020 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	$ 88.4	$ 88.9
$1,075 Million 5.75% 2025 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	1,073.3	1,075.0
$500 million 4.80% 2020 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	122.3	122.4
$700 Million 4.875% 2021 Senior Note [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	125.2	$ 138.4
Debt Repurchase [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	15.5
Debt Repurchase [Member] | $400 Million 5.90% 2020 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	0.5
Debt Repurchase [Member] | $1,075 Million 5.75% 2025 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	1.7
Debt Repurchase [Member] | $500 million 4.80% 2020 Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	0.1
Debt Repurchase [Member] | $700 Million 4.875% 2021 Senior Note [Member]
Debt Instrument [Line Items]
Debt Instrument, Par Value	$ 13.2