Earnings per Share (Details) (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
Numerator:
Loss from continuing operations	$ (24,988)	$ (9,507)	$ (17,837)	$ (11,641)
Net income attributable to non-controlling interest	(259)	(236)	(504)	(230)
Adjustment of estimated redemption value of non-controlling interest	276	0	0	0
Numerator for basic and diluted earnings per share from continuing operations - loss from continuing operations attributable to Headwaters Incorporated	(24,971)	(9,743)	(18,341)	(11,871)
Numerator for basic and diluted earnings per share from discontinued operations - income (loss) from discontinued operations, net of income taxes	(210)	(575)	(277)	125
Numerator for basic and diluted earnings per share - net loss attributable to Headwaters Incorporated	$ (25,181)	$ (10,318)	$ (18,618)	$ (11,746)
Denominator:
Denominator for basic earnings per share - weighted-average shares outstanding	73,555	73,121	73,501	73,094
Basic and diluted income (loss) per share from continuing operations (in dollars per share)	$ (0.34)	$ (0.13)	$ (0.25)	$ (0.16)
Basic and diluted income (loss) per share 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

Net income available to common stockholders after temporary equity accretion adjustments.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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- Definition

Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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- Definition

Amount of decrease to net income for accretion of temporary equity to its redemption value to derive net income apportioned to common stockholders.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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