Income Tax (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Income Taxes (Textual) ) [Abstract]
Provision for income taxes	$ 7,832	$ 9,880
Effective tax rate (as a percentage)	33.60%	34.20%
Liability for unrecognized tax benefits	413
Unrecognized tax benefits that would impact effective tax rate	413
Decrease in liability for unrecognized tax benefits due to the expiration of the statute of limitations of prior year tax positions of acquired companies	$ 71
Period within which the company does not anticipate total unrecognized tax benefits to change	within the next twelve months