Share-Based Compensation Arrangement by Share-Based Payment Award, Award Maximum Payout, Maximum Percentage

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- Definition

Share-Based Compensation Arrangement by Share-Based Payment Award, Award Performance Achievement Measurement Period

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Face amount or stated value per share of common stock.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The amount of plan compensation cost recognized during the period.

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The cash inflow from the additional capital contribution to the entity.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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Number of shares issued under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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Share-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands				3 Months Ended
	Oct. 01, 2021	Dec. 21, 2018	Oct. 01, 2018	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period				3 years
Granted (shares)				4
Intrinsic value, exercises in period				$ 2,014
Fair value of options vested				13
Share-based Compensation expense				6,317	$ 5,334
Non-cash share-based compensation				6,196	5,203
Compensation cost not yet recognized, period for recognition				28,304
Proceeds from issuance of common stock				$ 2,868	2,085
Employee Stock Ownership Plan (ESOP), Shares in ESOP		11,297
Common stock, par value (in dollars per share)				$ 0.01		$ 0.01
Evoqua Water Technologies Corp. Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards vesting percentage				25.00%
Contractual term of options				10 years
Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Maximum Payout, Maximum Percentage				250.00%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Performance Measurement Period				3 years
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity incentive plan, number of shares authorized (shares)				11,083
Number of shares available for grant (in shares)				2,177
Compensation cost not yet recognized, period for recognition				$ 3,841
Period for recognition for unrecognized compensation expense				1 year 2 months 12 days
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)				3,576
Purchase price of stock, percentage			85.00%
Employee Stock Ownership Plan (ESOP), Shares in ESOP		5,000
Employee Stock Ownership Plan (ESOP), Compensation Expense				$ 316	$ 221
Shares issued under ESPP	62
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value (in dollars per share)		$ 0.01
Special RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized, period for recognition				$ 14,929
Period for recognition for unrecognized compensation expense				1 year 9 months 18 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for recognition for unrecognized compensation expense				1 year 9 months 18 days