Earnings Per Share ("EPS") and Cash Dividends - Summary of Basic EPS and Diluted EPS Calculations (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share Diluted [Line Items]
Net income	$ 3,247	$ 5,877	$ 7,506	$ 9,719
Basic shares	13,458	13,273	13,415	13,231
Diluted shares	13,565	13,402	13,564	13,373
Basic EPS	$ 0.24	$ 0.44	$ 0.56	$ 0.73
Diluted EPS	$ 0.24	$ 0.44	$ 0.55	$ 0.73
Stock Options
Earnings Per Share Diluted [Line Items]
Incremental shares from the assumed exercise of outstanding stock options and lapse of restrictions on restricted stock awards	72	92	96	96
Restricted Stock
Earnings Per Share Diluted [Line Items]
Incremental shares from the assumed exercise of outstanding stock options and lapse of restrictions on restricted stock awards	35	37	53	46