Quarterly Financial Information (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Net sales	$ 151,413	$ 130,495	$ 124,762	$ 124,450	$ 144,600	$ 116,922	$ 118,039	$ 110,518	$ 531,120	$ 490,079	$ 478,699
Net earnings from continuing operations	12,927	11,590	9,264	8,832	13,880	6,514	5,523	5,343	42,613	31,260	34,774
Net (loss) earnings from discontinued operations	(1,619)	0	(42,941)	2,357	(46,185)	(1,617)	(3,964)	(5,097)	9,858	(56,863)	12,105
Net earnings (loss)	$ 11,308	$ 11,590	$ (33,677)	$ 11,189	$ (32,305)	$ 4,897	$ 1,559	$ 246	$ 410	$ (25,603)	$ 46,879
Basic earnings (loss) per share:
Net earnings from continuing operations	$ 0.49	$ 0.44	$ 0.35	$ 0.33	$ 0.52	$ 0.25	$ 0.21	$ 0.20	$ 1.61	$ 1.18	$ 1.30
Net (loss) earnings from discontinued operations	$ (0.06)	$ 0	$ (1.62)	$ 0.09	$ (1.75)	$ (0.06)	$ (0.15)	$ (0.19)	$ (1.60)	$ (2.15)	$ 0.46
Net earnings (loss)	$ 0.43	$ 0.44	$ (1.27)	$ 0.42	$ (1.23)	$ 0.19	$ 0.06	$ 0.01	$ 0.01	$ (0.97)	$ 1.76
Diluted earnings (loss) per share:
Net earnings from continuing operations	$ 0.49	$ 0.43	$ 0.35	$ 0.33	$ 0.52	$ 0.24	$ 0.21	$ 0.20	$ 1.60	$ 1.17	$ 1.29
Net (loss) earnings from discontinued operations	$ (0.06)	$ 0	$ (1.61)	$ 0.09	$ (1.73)	$ (0.06)	$ (0.15)	$ (0.19)	$ (1.58)	$ (2.13)	$ 0.44
Net earnings (loss)	$ 0.43	$ 0.43	$ (1.26)	$ 0.42	$ (1.21)	$ 0.18	$ 0.06	$ 0.01	$ 0.02	$ (0.96)	$ 1.73
Dividends declared per common share	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.32	$ 0.32	$ 0.32