CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2009
Current assets:
Cash and cash equivalents	$ 2,678	$ 5,525	$ 5,218	$ 2,545	$ 3,906	$ 3,463	$ 4,121	$ 4,552	$ 6,081	$ 4,149	$ 20,038
Restricted cash	8,084	3,751	3,599	129	1,612	1,774	1,813	628	460
Short-term investments	20,546	20,769	20,553	20,486	19,736	18,486	17,632	15,825	24,414
Accounts and notes receivable, net of allowance for doubtful accounts $1,115 and $1,872, respectively	43,922	42,793	43,752	43,139	40,736	41,685	44,765	44,554	43,501
Inventories	60,867	67,273	68,385	69,924	65,981	75,451	77,874	83,098	79,449
Income tax receivable	409	117	472	369	762	830	178	168	448
Prepaid expenses	3,243	2,800	2,740	3,091	3,445	2,791	3,196	2,249	2,747
Total current assets	139,749	143,028	144,719	139,683	136,178	144,480	149,579	151,074	157,100
Property, plant and equipment, net	92,159	93,838	98,160	103,317	108,137	106,855	105,031	108,944	114,340
Intangible assets, net	6,277	6,586	6,929	7,272	7,615	8,232	13,902	14,270	9,329
Other assets	5,484	5,247	5,273	5,358	5,125	4,839	4,877	4,919	4,963
Deferred income taxes	467	861	861	861	861	1,007	1,007	1,007	1,008
Total assets	244,136	249,560	255,942	256,491	257,916	270,723	274,396	280,214	292,050
Current liabilities:
Accounts payable	27,740	29,878	30,453	29,196	27,266	31,688	39,818	38,146	42,422
Accrued payroll expenses	19,757	15,372	17,009	18,341	19,130	18,040	18,525	16,171	16,958
Short-term borrowings under revolving credit facility	9,654	9,912	15,074	24,996	29,126	28,702	25,971	33,398	31,362
Short-term obligations under capital leases	3,409	3,435	3,527	3,683	3,737	2,745	1,674	1,588	1,570
Short term derivative liability	9,896	5,916	6,292	29	737	2,585	794	3,283	1,729
Deferred income taxes	923	1,445	1,445	1,445	1,445	476	476	476	476
Other current liabilities	5,171	6,728	5,242	5,268	5,296	5,287	4,276	4,063	4,527
Total current liabilities	76,550	72,686	79,042	82,958	86,737	89,523	91,534	97,125	99,044
Long-term borrowings under revolving credit facility	10,000	10,000	10,000		0
Long-term derivative liability	1,129				0
Accrued postretirement benefits	16,076	22,989	22,878	22,815	22,526	19,239	19,172	19,027	18,996
Other long-term liabilities-capital leases	8,759	9,552	10,617	11,368	12,130	9,759	6,254	6,664	7,066
Accrued pension liabilities	43,800	47,651	47,456	47,217	48,191	26,909	28,173	24,993	28,048
Accrued workers' compensation liabilities	5,132	4,022	4,022	4,131	4,131	3,821	3,624	3,639	3,639
Deferred income taxes	852	759	648	649	649	1,842	1,842	1,842	1,842
Total liabilities	162,298	167,659	174,663	169,138	174,364	151,093	150,599	153,290	158,635
Commitments and contingencies
Stockholders' equity:
Preferred stock, $1.00 par value, 500,000 shares authorized and none issued	0	0	0	0	0	0	0	0	0
Common stock, $1.00 par value, 25,000,000 shares authorized; 16,454,422 and 16,308,859 shares issued and outstanding at June 30, 2013 and 2012, respectively	16,454	16,449	16,342	16,314	16,309	16,281	16,262	16,187	16,186
Additional paid-in capital	34,654	33,728	31,906	35,653	34,834	34,093	33,071	37,259	36,470
Retained earnings	94,080	97,056	98,363	105,519	102,542	112,814	118,023	121,837	129,118
Unearned ESOP shares	(20,836)	(20,836)	(20,836)	(25,637)	(25,637)	(25,636)	(25,637)	(30,437)	(30,437)
Less accumulated other comprehensive loss	(42,514)	(44,496)	(44,496)	(44,496)	(44,496)	(17,922)	(17,922)	(17,922)	(17,922)
Total stockholders' equity	81,838	81,901	81,279	87,353	83,552	119,630	123,797	126,924	133,415	161,744
Total liabilities and stockholders' equity	$ 244,136	$ 249,560	$ 255,942	$ 256,491	$ 257,916	$ 270,723	$ 274,396	$ 280,214	$ 292,050