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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The net total number of shares (or other type of equity) under an equity-based award plan, other than a stock option plan, that were granted, vested and forfeited during the reporting period.

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STOCK-BASED COMPENSATION: Non vested time vesting restricted stock unit activity (Details) - Restricted stock units - USD ($) $ / shares in Units, $ in Millions	9 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018
Restricted Stock Unit Activity - Other disclosures
Share-based compensation expense	$ 34.6	$ 21.6
Time Based Vesting
Non-vested restricted stock unit activity
Outstanding at the beginning of the period (in shares)	2,702,497
Granted (in shares)	1,877,874
Vested (in shares)	(1,363,871)
Forfeited or cancelled (in shares)	(265,878)
PSUs converted to RSUs in conjunction with AMS disposition (in shares)	1,017,422
Outstanding at the end of the period (in shares)	3,968,044		2,702,497
Non-vested restricted stock units, Weighted average fair value per share at grant date
Outstanding at the beginning of the period (in dollars per share)	$ 24.60
Granted (in dollars per share)	33.66
Vested (in dollars per share)	24.60
Forfeited or cancelled (in dollars per share)	25.39
PSUs converted to RSUs in conjunction with AMS disposition (in dollars per share)	21.21
Outstanding at the end of the period (in dollars per share)	$ 27.97		$ 24.60
Weighted-average remaining contractual term
Weighted average remaining contractual term (in years)	2 years 4 months 13 days		2 years 4 months 2 days
Restricted Stock Unit Activity - Other disclosures
Aggregate fair value of restricted stock units granted	$ 63.2
Total fair value	$ 54.4
Performance stock
Non-vested restricted stock unit activity
Outstanding at the beginning of the period (in shares)	561,018
Granted (in shares)	516,954
Additional earned performance shares (in shares)	176
Vested (in shares)	(61,330)
Forfeited or cancelled (in shares)	(129,501)
PSUs converted to RSUs in conjunction with AMS disposition (in shares)	(508,711)
Outstanding at the end of the period (in shares)	378,606		561,018
Non-vested restricted stock units, Weighted average fair value per share at grant date
Outstanding at the beginning of the period (in dollars per share)	$ 25.68
Granted (in dollars per share)	40.82
Additional earned performance shares (in dollars per share)	23.89
Vested (in dollars per share)	24.22
Forfeited or cancelled (in dollars per share)	25.15
PSUs converted to RSUs in conjunction with AMS disposition (in dollars per share)	28.08
Outstanding at the end of the period (in dollars per share)	$ 43.55		$ 25.68
Weighted-average remaining contractual term
Weighted average remaining contractual term (in years)	3 years 5 months 12 days		2 years 6 months 10 days
Restricted Stock Unit Activity - Other disclosures
Aggregate fair value of restricted stock units granted	$ 21.1
Performance Shares Vesting Total Shareholder Return
Non-vested restricted stock unit activity
Granted (in shares)	186,539
Restricted Stock Unit Activity - Other disclosures
Aggregate fair value of restricted stock units granted	$ 5.8
Performance Shares Vesting Under The Second Plan
Non-vested restricted stock unit activity
Granted (in shares)	330,415
Restricted Stock Unit Activity - Other disclosures
Aggregate fair value of restricted stock units granted	$ 15.3
Share-based Compensation Award, Tranche One
Restricted Stock Unit Activity - Other disclosures
Future share-based compensation expense expected	12.5
Share-based Compensation Award, Tranche Two
Restricted Stock Unit Activity - Other disclosures
Future share-based compensation expense expected	42.5
Share-based Compensation Award, Tranche Three
Restricted Stock Unit Activity - Other disclosures
Future share-based compensation expense expected	27.9
Share-based Compensation Award, Tranche Four
Restricted Stock Unit Activity - Other disclosures
Future share-based compensation expense expected	15.6
Share-based Compensation Award, Tranche Five
Restricted Stock Unit Activity - Other disclosures
Future share-based compensation expense expected	$ 4.2
Vesting in four years
Non-vested restricted stock unit activity
Granted (in shares)	197,115
Restricted Stock Unit Activity - Other disclosures
Vesting period	4 years
Partial cliff vest tranche one
Non-vested restricted stock unit activity
Granted (in shares)	1,272,337
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	25.00%
Partial cliff vesting tranche two
Non-vested restricted stock unit activity
Granted (in shares)	330,415
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	50.00%
Vesting in three years
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	75.00%
Vesting period	3 years
Vesting in two years
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	50.00%
Vesting period	2 years
Vesting in one year
Non-vested restricted stock unit activity
Granted (in shares)	78,007
Restricted Stock Unit Activity - Other disclosures
Vesting period	1 year
Minimum \| Performance Shares Vesting Total Shareholder Return
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	25.00%
Minimum \| Performance Shares Vesting Under The Second Plan
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	0.00%
Maximum \| Performance Shares Vesting Total Shareholder Return
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	200.00%
Maximum \| Performance Shares Vesting Under The Second Plan
Restricted Stock Unit Activity - Other disclosures
Vesting percentage	200.00%