Quarterly report pursuant to Section 13 or 15(d)

NET INCOME (LOSS) PER SHARE - Anti-dilutive shares excluded from the computations of diluted net income (loss) (Details)

v3.8.0.1
NET INCOME (LOSS) PER SHARE - Anti-dilutive shares excluded from the computations of diluted net income (loss) (Details) - USD ($)
shares in Millions, $ in Millions
 3 Months Ended 6 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2012
Weighted average shares excluded:          
Interest expense excluded $ 0.6 $ 0.1 $ 1.4 $ 0.4  
Stock options          
Weighted average shares excluded:          
Weighted average shares excluded (shares) 0.2 0.2 0.2 0.4  
Unvested restricted stock units          
Weighted average shares excluded:          
Weighted average shares excluded (shares) 2.0 0.4 1.8 0.8  
4.50% convertible subordinated notes          
Weighted average shares excluded:          
Stated interest rate 4.50%   4.50%   4.50%
Convertible subordinated debt | 4.50% convertible subordinated notes          
Weighted average shares excluded:          
Weighted average shares excluded (shares) 4.3 5.3 4.3 5.1  
Stated interest rate 4.50%   4.50%