Equity and Compensation Plans - Additional Information (Detail) (USD $)	1 Months Ended				1 Months Ended				6 Months Ended
	May 31, 2013	Mar. 31, 2013	Mar. 31, 2012	Aug. 31, 2013	Mar. 31, 2013 Restricted Stock	May 31, 2012 Restricted Stock	Mar. 31, 2012 Restricted Stock	Aug. 31, 2013 2012 Plan CompensationPlan	Aug. 31, 2013 2012 Plan Minimum	Aug. 31, 2013 2012 Plan Maximum	Aug. 31, 2013 2012 Plan Stock Options	Aug. 31, 2013 2012 Plan Restricted Stock Minimum	Aug. 31, 2013 2012 Plan Restricted Stock Maximum	Aug. 31, 2013 2001 Directors Plan CompensationPlan	Sep. 30, 2012 Non-employee directors Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of active equity award plan								1
Shares authorized under compensation plans								2,130,789
Share based payment award, award vesting period					1 year	3 years	1 year				3 years	3 years	5 years
Non-qualified stock options, expiration period from date of grant									5 years	10 years
Number of inactive equity award plans														1
Stock options outstanding and exercisable														3,537
Share based payment award, stock option granted		100,000	200,000
Share based payment award, value of each option granted		$ 4.70	$ 4.24
Options exercised	67,680
Share based payment award, stock options outstanding				720,458
Share based payment award, stock options exercisable				220,458
Share based payment award, restricted stock issued					2,100	10,000	5,900
Vested shares							5,754
Forfeited shares							146
Share based payment award, stock option granted															$ 8,500