Stock-Based Compensation (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Compensation Expense [Abstract]
Stock-based compensation cost	$ 3.6	$ 3.1	$ 1.6
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option term	10 years
Assumptions for stock options granted [Abstract]
Weighted average fair value of options (in dollars per share)	$ 7.76	$ 4.26	$ 10.45
Expected life of awards in years	6 years 3 months 18 days	6 years 3 months 18 days	6 years 3 months 18 days
Risk-free interest rate (in hundredths)	1.30%	0.90%	1.90%
Expected volatility of the Company's stock (in hundredths)	88.70%	87.40%	79.60%
Expected dividend yield on the Company's stock (in hundredths)	0.00%	0.00%	0.00%
Vesting percentage at grant date (in hundredths)	25.00%
Annual vesting percentage (in hundredths)	25.00%
Pre-vesting forfeiture rate (in hundredths)	2.50%
Compensation Expense [Abstract]
Stock-based compensation cost	0.8	1.1	1.3
Total fair value of stock options vesting	0.8
Unrecognized compensation costs	1.3
Weighted average period recognized	2 years 7 months 6 days
Shares [Rollforward]
Outstanding, April 1 (in shares)	1.7
Granted (in shares)	0.2
Exercised (in shares)	(0.2)
Forfeited or expired (in shares)	(0.1)
Outstanding, March 31 (in shares)	1.6	1.7
Exercisable, March 31 (in shares)	1.3
Weighted average exercise price [Rollforward]
Outstanding, April 1 (in dollars per share)	$ 14.03
Granted (in dollars per share)	$ 10.40
Exercised (in dollars per share)	$ 6.71
Forfeited or expired (in dollars per share)	$ 25.37
Outstanding, March 31 (in dollars per share)	$ 13.15	$ 14.03
Exercisable, March 31 (in dollars per share)	$ 14.15
Options, Outstanding, Weighted average remaining contractual term	5 years 6 months
Options, Outstanding, Aggregate intrinsic value	7.4
Options, Exercisable, Weighted average remaining contractual term	4 years 8 months 12 days
Options, Exercisable, Aggregate intrinsic value	5.6
Additional information related to stock options exercised [Abstract]
Intrinsic value of stock options exercised	1.1	0.1	0.2
Proceeds from stock options exercised	1.1	0.1	0.5
Restricted Stock [Member]
Compensation Expense [Abstract]
Stock-based compensation cost	2.2	1.8	1.1
Unrecognized compensation costs	3.9
Weighted average period recognized	2 years 8 months 12 days
Shares [Roll Forward]
Non-vested balance, April 1 (in shares)	0.5
Granted (in shares)	0.3
Vested (in shares)	(0.2)
Non-vested balance, March 31 (in shares)	0.6	0.5
Weighted average price [Rollforward]
Non-vested balance, April 1 (in dollars per share)	$ 6.91
Granted (in dollars per share)	$ 10.95
Vested (in dollars per share)	$ 8.67
Non-vested balance, March 31 (in dollars per share)	$ 8.66	$ 6.91
Restricted Stock - Performance Based Shares [Member]
Compensation Expense [Abstract]
Stock-based compensation cost	0.6	0.2	(0.8)
Unrecognized compensation costs	$ 1.7
Weighted average period recognized	2 years
Restricted Stock - Performance-Based Shares [Abstract]
Award performance period	3 years
2008 Incentive Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	1.8