Condensed Consolidating Financial Information (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities:
Net income (loss)	$ (8,260)		$ (20,558)	$ (14,132)	$ (44,306)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization				25,582	26,196
Interest expense related to amortization of debt issue costs and debt discount	1,900		2,800	3,165	5,863
Stock-based compensation	400		300	821	923
Deferred income taxes				55	27
Net gain on disposition of property, plant and equipment				(673)	(429)
Gain on sale of discontinued operations, net of income taxes				(3,110)	0
Gain on convertible debt repayment				(35)	(2,025)
Non-cash restructuring costs				0	971
Net loss of unconsolidated joint ventures				0	6,069
Decrease in trade receivables				31,676	23,245
Increase in inventories				(5,960)	(717)
Decrease in accounts payable and accrued liabilities				(28,334)	(15,043)
Other changes in operating assets and liabilities, net				(8,098)	7,270
Net cash provided by operating activities				957	8,044
Cash flows from investing activities:
Payment for acquisition				(43,250)	0
Purchase of property, plant and equipment	(7,854)		(5,213)	(14,407)	(11,832)
Proceeds from disposition of property, plant and equipment				789	1,093
Proceeds from sale of discontinued operations				3,813	0
Proceeds from sale of interests in joint ventures				0	8,636
Net change in other assets				(1,265)	(1,514)
Net cash used in investing activities				(54,320)	(3,617)
Cash flows from financing activities:
Net proceeds from issuance of common stock		78,000		77,957	0
Payments on long-term debt				(15,217)	(17,441)
Employee stock purchases				454	284
Net cash provided by (used in) financing activities				63,194	(17,157)
Net increase (decrease) in cash and cash equivalents				9,831	(12,730)
Cash and cash equivalents, beginning of period		53,782		53,782	50,810
Cash and cash equivalents, end of period	63,613		38,080	63,613	38,080
Guarantor Subsidiaries
Cash flows from operating activities:
Net income (loss)	5,172		2,429	12,712	(6,505)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization				25,449	26,140
Stock-based compensation				381	349
Deferred income taxes				55	29
Net gain on disposition of property, plant and equipment				(673)	(429)
Gain on sale of discontinued operations, net of income taxes				(3,110)
Non-cash restructuring costs					971
Net loss of unconsolidated joint ventures					6,069
Decrease in trade receivables				31,676	23,245
Increase in inventories				(5,960)	(717)
Decrease in accounts payable and accrued liabilities				(20,707)	(13,732)
Other changes in operating assets and liabilities, net				22,303	(43,379)
Net cash provided by operating activities				62,126	(7,959)
Cash flows from investing activities:
Payment for acquisition				(43,250)
Purchase of property, plant and equipment				(13,220)	(11,625)
Proceeds from disposition of property, plant and equipment				789	1,093
Proceeds from sale of discontinued operations				3,813
Proceeds from sale of interests in joint ventures					8,636
Net change in other assets				(1,785)	(2,732)
Net cash used in investing activities				(53,653)	(4,628)
Cash flows from financing activities:
Employee stock purchases				319	251
Net cash provided by (used in) financing activities				319	251
Net increase (decrease) in cash and cash equivalents				8,792	(12,336)
Cash and cash equivalents, beginning of period		44,111		44,111	36,122
Cash and cash equivalents, end of period	52,903		23,786	52,903	23,786
Parent Company
Cash flows from operating activities:
Net income (loss)	(13,432)		(22,987)	(26,844)	(37,801)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization				133	56
Interest expense related to amortization of debt issue costs and debt discount				3,165	5,863
Stock-based compensation				440	574
Deferred income taxes					(2)
Gain on convertible debt repayment				(35)	(2,025)
Decrease in accounts payable and accrued liabilities				(7,627)	(1,311)
Other changes in operating assets and liabilities, net				(30,401)	50,649
Net cash provided by operating activities				(61,169)	16,003
Cash flows from investing activities:
Purchase of property, plant and equipment				(1,187)	(207)
Net change in other assets				520	1,218
Net cash used in investing activities				(667)	1,011
Cash flows from financing activities:
Net proceeds from issuance of common stock				77,957
Payments on long-term debt				(15,217)	(17,441)
Employee stock purchases				135	33
Net cash provided by (used in) financing activities				62,875	(17,408)
Net increase (decrease) in cash and cash equivalents				1,039	(394)
Cash and cash equivalents, beginning of period		9,671		9,671	14,688
Cash and cash equivalents, end of period	$ 10,710		$ 14,294	$ 10,710	$ 14,294