STOCKHOLDERS' EQUITY - VARIOUS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stockholders Equity Note [Line Items]
Anti-dilutive securities excluded from determination of diluted earnings per common share	200,000	600,000	100,000
Restricted stock units granted	176,000	727,000
Restricted stock units forfeited	108,000	163,000
Outstanding restricted stock units	1,026,000	1,522,000	1,545,000
Outstanding stock options	0	0	0
Stock options exercised			29,750
Stock options exercised, aggregate intrinsic value			$ 2.0
Restricted Stock
Stockholders Equity Note [Line Items]
Share based compensation	$ 35.2	$ 28.7	28.1
Unrecognized compensation cost	$ 75.5	$ 71.1	$ 59.9
Restricted Stock | Minimum
Stockholders Equity Note [Line Items]
Restricted stock and restricted stock unit grants, vesting period	3 years
Restricted Stock | Maximum
Stockholders Equity Note [Line Items]
Restricted stock and restricted stock unit grants, vesting period	4 years
Restricted Stock | Deferred Compensation Plan
Stockholders Equity Note [Line Items]
Restricted stock units granted	6,242	7,146	16,148
Restricted stock units forfeited	0
Weighted average remaining vesting period	2 years 3 months 4 days
Outstanding restricted stock units	16,165
Time And Performance Based Restricted Stock
Stockholders Equity Note [Line Items]
Restricted stock units granted	486,746	243,840
Restricted stock units forfeited	0
Weighted average remaining vesting period	3 years 26 days
Outstanding restricted stock units	688,973