Summary of Changes of Non-Vested Options (Detail) (USD $)	12 Months Ended
Mar. 31, 2013
Number of options
Nonvested, Number of Options, Beginning Balance	110,037
Number of Options, Vested	(110,037)
Weighted average grant-date fair value
Weighted Average Grant-Date Fair Value, Nonvested, Beginning Balance	$ 7.87
Weighted Average Grant-Date Fair Value, Vested	$ 7.87

Share based compensation arrangement by share based payment award, nonvested options, weighted average grant date fair value vested

No definition available.

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Namespace Prefix:	ens_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration