Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Mar. 31, 2012
Recorded value [Member] | BEP Current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Liabilities:		$ 2,948
Recorded value [Member] | Available-for-sale Securities [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring		4,408
Recorded value [Member] | Corporate owned life insurance non-current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring	3,555	3,458
Active markets for identical assets or liabilities (Level 1) [Member] | BEP Current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Liabilities:		0
Active markets for identical assets or liabilities (Level 1) [Member] | Available-for-sale Securities [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring		4,408
Active markets for identical assets or liabilities (Level 1) [Member] | Corporate owned life insurance non-current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring	0	0
Quoted prices in similar instruments and observable inputs (Level 2) [Member] | BEP Current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Liabilities:		2,948
Quoted prices in similar instruments and observable inputs (Level 2) [Member] | Available-for-sale Securities [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring		0
Quoted prices in similar instruments and observable inputs (Level 2) [Member] | Corporate owned life insurance non-current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring	0	0
Active markets for unobservable inputs (Level 3) [Member] | BEP Current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Liabilities:		0
Active markets for unobservable inputs (Level 3) [Member] | Available-for-sale Securities [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring		0
Active markets for unobservable inputs (Level 3) [Member] | Corporate owned life insurance non-current [Member]
Financial assets and liabilities measured at fair value on a recurring basis
Assets, Fair Value Disclosure, Recurring	$ 3,555	$ 3,458