Stockholders' Equity (Schedule of Assumptions Used in Estimate of Fair Value of Stock Option Awards) (Details) - $ / shares	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date market value of Woodward stock	$ 78.91	$ 69.45	$ 40.26
Weighted-average exercise price per share	78.91	62.74	40.26
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date market value of Woodward stock	78.91	69.45	40.26
Weighted-average exercise price per share	$ 78.91	$ 62.74	$ 40.26
Expected term	6 years 4 months 24 days	6 years	6 years 3 months 18 days
Estimated volatility	29.10%	30.60%	34.50%
Estimated dividend yield	0.60%	0.70%	1.00%
Risk-free interest rate	2.10%	2.00%	1.70%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	8 years 8 months 12 days	8 years 8 months 12 days	8 years 8 months 12 days
Estimated volatility	32.70%	33.70%	35.10%
Estimated dividend yield	0.80%	0.70%	1.00%
Risk-free interest rate	2.80%	2.50%	2.00%

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

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.

+ References

No definition available.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. Weighted average price for all grants during the period.

+ References

No definition available.

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company used in the fair value assumptions. Weighted average price for grants during the period.

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No definition available.

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