Share Based Awards (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Summary of Stock Option Activity
Number of Shares Outstanding Beginning Balance	988	1,398	1,744
Weighted Average Exercise Price Outstanding Beginning Balance	$ 30	$ 20	$ 20
Weighted Average Remaining Contractual Life Outstanding Beginning Balance	5 years 6 months	5 years 4 months 24 days
Number of Share Granted	557	459	110
Weighted Average Exercise Price Granted	$ 30	$ 40	$ 30
Weighted Average Remaining Contractual Life Granted	7 years 2 months 12 days
Number of Shares Exercised	56	697	307
Weighted Average Exercise Price Exercised	$ 20	$ 20	$ 20
Weighted Average Remaining Contractual Life Exercised	3 months 18 days
Aggregate Intrinsic Value, Exercised	$ 82	$ 17,698	$ 7,093
Number of Shares Forfeited/Canceled	329	171	149
Weighted Average Exercise Price Forfeited/Canceled	$ 30	$ 40	$ 30
Weighted Average Remaining Contractual Life Forfeited/Canceled	5 years 9 months 18 days
Number of Shares Outstanding Ending Balance	1,159	988	1,398
Weighted Average Exercise Price Outstanding Ending Balance	$ 30	$ 30	$ 20
Weighted Average Remaining Contractual Life Outstanding Ending Balance	5 years 6 months	5 years 4 months 24 days
Aggregate Intrinsic Value Outstanding Ending Balance	31
Number of Shares Vested and expected to vest	1,096
Weighted Average Exercise Price Vested and expected to vest	$ 30
Weighted Average Remaining Contractual Life Vested and expected to vest	5 years 6 months
Aggregate Intrinsic Value Vested and expected to vest	31
Number of Shares Exercisable	355
Weighted Average Exercise Price Exercisable	$ 30
Weighted Average Remaining Contractual Life Exercisable	3 years 3 months 18 days
Aggregate Intrinsic Value Exercisable	$ 29