Stock-Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense, net of tax	$ 424	$ 446	$ 392
Shares of common stock granted	558,113
Options vesting period, beginning one year after the date of the grant	3 years
Number of Shares, Granted	158,000	551,000	184,000
Options valued by Black Scholes pricing model	19,000	77,000
Weighted-Average Exercise Price, Granted	$ 8.58	$ 8.07	$ 8.64
Exercise of stock options	912	161	194
Common stock received in lieu of cash payment for stock option exercises		14,739
Aggregate intrinsic value of options exercised	253	35	78
Unrecognized compensation cost related to stock options granted-but-not-yet-vested that are expected to become exercisable	597
Weighted-average period cost is to be recognized	1 year
Forfeiture provisions lapse period for non-employee directors	1 year
Transfer restrictions lapse period for non-employee directors	6 months
Unrecognized compensation cost related to non-vested restricted stock awards	152
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option compensation expense	468	626	330
Taxes related to stock option compensation expense	173	283	138
Weighted-average period cost is to be recognized	1 year
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option compensation expense	204	187	345
Taxes related to stock option compensation expense	$ 76	$ 84	$ 145
Black Scholes Based Option Pricing Model | 2014 $3.03 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 3.03
Black Scholes Based Option Pricing Model | 2014 $3.01 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 3.01
Black Scholes Based Option Pricing Model | 2013 $3.05 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 3.05	$ 3.05
Black Scholes Based Option Pricing Model | 2013 $3.02 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 3.02	$ 3.02
Black Scholes Based Option Pricing Model | 2013 $3.02 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 3.02	$ 3.02
Black Scholes Based Option Pricing Model | 2013 $2.82 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 2.82	$ 2.82
Black Scholes Based Option Pricing Model | 2012 $2.75 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 2.75		$ 2.75
Black Scholes Based Option Pricing Model | 2012 $2.58 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 2.58		$ 2.58
Black Scholes Based Option Pricing Model | 2012 $2.72 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 2.72		$ 2.72
Black Scholes Based Option Pricing Model | 2012 $2.81 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 2.81		$ 2.81
Black Scholes Based Option Pricing Model | 2012 $2.13 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 2.13		$ 2.13
Monte Carlo Simulation
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Granted	139,000	474,000
Monte Carlo Simulation | 2014 $1.90 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 1.90
Monte Carlo Simulation | 2014 $1.71 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 1.71
Monte Carlo Simulation | 2013 $1.86 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 1.86	$ 1.86
Monte Carlo Simulation | 2013 $1.75 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 1.75	$ 1.75
Monte Carlo Simulation | 2013 $1.75 Value Per Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average value per option granted	$ 1.75	$ 1.75
Chief Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Granted	400,000
Exercise price, options	$ 8.10
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period	10 years
2012 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock granted	750,000
Shares of common stock granted, expiration date	Oct. 31, 2022
2006 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock granted	500,000
Shares of common stock granted, expiration date	Jul. 31, 2016
2004 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock granted	200,000
Shares of common stock granted, expiration date	Sep. 30, 2014