Earnings Per Share - Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Numerator:
Income from continuing operations	$ 6,675	$ 12,937
Income from continuing operations attributable to non-controlling interest	(161)	(296)
Numerator for basic and diluted earnings per share from continuing operations — income from continuing operations attributable to Headwaters Incorporated	6,514	12,641
Numerator for basic and diluted earnings per share from discontinued operations - income (loss) from discontinued operations, net of income taxes	153	(216)
Numerator for basic and diluted earnings per share — net income attributable to Headwaters Incorporated	$ 6,667	$ 12,425
Denominator:
Denominator for basic earnings per share - weighted-average shares outstanding	74,237	73,789
Effect of dilutive securities - shares issuable upon exercise of options and SARs and vesting of restricted stock	1,435	1,576
Denominator for diluted earnings per share - weighted-average shares outstanding after assumed exercises and vesting	75,672	75,365
Basic and diluted income per share attributable to Headwaters Incorporated
From continuing operations (in dollars per share)	$ 0.09	$ 0.17
From discontinued operations (in dollars per share)	0.00	0.00
Basic and diluted income per share (in dollars per share)	$ 0.09	$ 0.17

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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Amount after tax of income (loss) from continuing operations attributable to the parent.

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Amount after tax of income (loss) from continuing operations including portion attributable to the 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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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to 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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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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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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