Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended						1 Months Ended	3 Months Ended	1 Months Ended	3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Fiscal 2011 beginning on October 1, 2010 and ending on September 30, 2013 [Member]	Jun. 30, 2013 Fiscal 2012 beginning on October 1, 2011 and ending on September 30, 2014 [Member]	Jun. 30, 2013 Fiscal 2013 beginning on October 1, 2012 and ending on September 30, 2015 [Member]	Jun. 30, 2013 Non-qualified stock options granted subsequent to April 2008 [Member]	Dec. 12, 2012 Restricted Stock Units (RSUs) [Member]	Jun. 30, 2013 Restricted Stock Units (RSUs) [Member]	Sep. 30, 2000 Maximum [Member]	Jun. 30, 2013 Maximum [Member]	Jun. 30, 2012 Maximum [Member]	Jun. 30, 2013 Maximum [Member]	Jun. 30, 2012 Maximum [Member]	Jun. 30, 2013 Maximum [Member] Nonqualified Stock Options [Member]	Jun. 30, 2013 Minimum [Member]	Jun. 30, 2013 Minimum [Member] Nonqualified Stock Options [Member]
Stock Based Compensation Activity [Line Items]
Unrecognized compensation costs related to non-vested awards	$ 4,000,000		$ 4,000,000
Weighted average period for recognition of compensation costs related to non-vested awards			2 years 8 months 12 days
Performance Share Awards Fully Expensed	1,300,000		1,300,000
Weighted average per share fair value of stock options		$ 5.94	$ 8.69	$ 5.24
Stock option granted	0
Dividend yield		0.00%	0.00%	0.00%
Stock option expiration term upon expiration of employment or service																10 years		7 years
Percentage of non-qualified stock options on each of first four anniversaries								25.00%
Total pre-tax intrinsic value of options exercised	26,000		51,000	49,000
Stock option exercised		0
Restricted stock expenses												100,000	100,000	100,000	200,000
Expenses recognized related to Performance Shares	300,000	400,000	900,000	700,000
Performance Shares, time period			3 years
Performance period start date					Oct. 01, 2010	Oct. 01, 2011	Oct. 01, 2012
Performance period end date					Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2015
Targeted number of shares to be vested upon achievement of all or portion of performance objectives during the performance period					68,533	62,497	42,753
Performance share awards, estimated vesting percentage												200.00%					20.00%
Common stock authorized, shares											400,000
Annual compensation withheld											10.00%
Annual compensation withheld, maximum limit											25,000
Employee contributions	100,000		100,000										100,000		100,000
Stock compensation expenses recognized			100,000	100,000								100,000	100,000
Number of restricted stock units awarded									11,776	3,994
Number of restricted stock issued value										92,000
RSU award vest each year									33.00%
RSU expenses			$ 100,000									$ 100,000