CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Revenue:
Total revenue	$ 179,725us-gaap_Revenues	$ 156,512us-gaap_Revenues	$ 379,322us-gaap_Revenues	$ 322,127us-gaap_Revenues
Cost of revenue:
Total cost of revenue	132,584us-gaap_CostOfRevenue	117,961us-gaap_CostOfRevenue	276,494us-gaap_CostOfRevenue	242,683us-gaap_CostOfRevenue
Gross profit	47,141us-gaap_GrossProfit	38,551us-gaap_GrossProfit	102,828us-gaap_GrossProfit	79,444us-gaap_GrossProfit
Operating expenses:
Amortization	4,560us-gaap_AmortizationOfDeferredCharges	5,485us-gaap_AmortizationOfDeferredCharges	9,046us-gaap_AmortizationOfDeferredCharges	10,591us-gaap_AmortizationOfDeferredCharges
Selling, general and administrative	34,351	32,517	66,380	60,744
Total operating expenses	38,911us-gaap_OperatingExpenses	38,002us-gaap_OperatingExpenses	75,426us-gaap_OperatingExpenses	71,335us-gaap_OperatingExpenses
Operating income	8,230us-gaap_OperatingIncomeLoss	549us-gaap_OperatingIncomeLoss	27,402us-gaap_OperatingIncomeLoss	8,109us-gaap_OperatingIncomeLoss
Other income (expense):
Net interest expense	(35,965)us-gaap_InterestIncomeExpenseNet	(12,234)us-gaap_InterestIncomeExpenseNet	(47,917)us-gaap_InterestIncomeExpenseNet	(22,290)us-gaap_InterestIncomeExpenseNet
Other, net	(33)us-gaap_OtherNonoperatingIncomeExpense	(32)us-gaap_OtherNonoperatingIncomeExpense	(302)us-gaap_OtherNonoperatingIncomeExpense	(20)us-gaap_OtherNonoperatingIncomeExpense
Total other income (expense), net	(35,998)us-gaap_NonoperatingIncomeExpense	(12,266)us-gaap_NonoperatingIncomeExpense	(48,219)us-gaap_NonoperatingIncomeExpense	(22,310)us-gaap_NonoperatingIncomeExpense
Loss from continuing operations before income taxes	(27,768)	(11,717)	(20,817)	(14,201)
Income tax benefit	2,780us-gaap_IncomeTaxExpenseBenefit	2,210us-gaap_IncomeTaxExpenseBenefit	2,980us-gaap_IncomeTaxExpenseBenefit	2,560us-gaap_IncomeTaxExpenseBenefit
Loss from continuing operations	(24,988)	(9,507)	(17,837)	(11,641)
Income (loss) from discontinued operations, net of income taxes	(210)	(575)	(277)	125
Net loss	(25,198)us-gaap_ProfitLoss	(10,082)us-gaap_ProfitLoss	(18,114)us-gaap_ProfitLoss	(11,516)us-gaap_ProfitLoss
Net income attributable to non-controlling interest	(259)	(236)	(504)	(230)
Net loss attributable to Headwaters Incorporated	(25,457)us-gaap_NetIncomeLoss	(10,318)us-gaap_NetIncomeLoss	(18,618)us-gaap_NetIncomeLoss	(11,746)us-gaap_NetIncomeLoss
Basic and diluted income (loss) per share attributable to Headwaters Incorporated:
From continuing operations (in dollars per share)	$ (0.34)	$ (0.13)	$ (0.25)	$ (0.16)
From discontinued operations (in dollars per share)	$ 0.00	$ (0.01)	$ 0.00	$ 0.00
Earnings (loss) per share, basic and diluted, total (in dollars per share)	$ (0.34)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.14)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.25)us-gaap_EarningsPerShareBasicAndDiluted	$ (0.16)us-gaap_EarningsPerShareBasicAndDiluted
Building Products
Revenue:
Total revenue	106,406	94,139	223,940	187,151
Cost of revenue:
Total cost of revenue	79,481	70,828	163,673	140,166
Construction Materials
Revenue:
Total revenue	67,498	59,093	148,902	130,614
Cost of revenue:
Total cost of revenue	50,738	45,669	110,249	100,434
Energy Technology
Revenue:
Total revenue	5,821	3,280	6,480	4,362
Cost of revenue:
Total cost of revenue	$ 2,365	$ 1,464	$ 2,572	$ 2,083

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