Retirement Benefits (Narrative) (Details) shares in Thousands	12 Months Ended
	Sep. 30, 2017 USD ($) shares	Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($) shares
Defined Benefit Plan Disclosure [Line Items]
Value of Company Stock Contributed to Defined Contribution Benefit Plans	$ 14,014,000	$ 13,999,000	$ 12,574,000
Treasury Stock Issued During Period, Shares, Employee Benefit Plans | shares	199	317	259
Woodward Retirement Savings Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares of Woodward stock held in Woodward Retirement Savings Plan | shares	4,183	4,488
Accrued Employee Benefits, Current	$ 11,355,000	$ 11,314,000
Total stockholders equity
Defined Benefit Plan Disclosure [Line Items]
Value of Company Stock Contributed to Defined Contribution Benefit Plans	14,014,000	13,999,000	$ 12,574,000
Treasury Stock at Cost [Member]
Defined Benefit Plan Disclosure [Line Items]
Value of Company Stock Contributed to Defined Contribution Benefit Plans	$ 7,513,000	$ 8,680,000	$ 8,084,000
Treasury Stock Issued During Period, Shares, Employee Benefit Plans | shares	199	317	259
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Settlement loss	$ 0	$ 47,000	$ 0
Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions in the next fiscal year	3,871,000
Accumulated benefit obligation	$ 32,252,000	35,630,000
Option to elect company provided medical insurance coverage up to this age and a Medicare supplemental plan after this age	65
Age employees were eligible to participate in plan	55
Years of service required to be eligible to participate in plan	10 years
Approximate number of retired employees and their covered dependents and beneficiaries currently providing postretirement benefits	770
Approximate number of active employees and their covered dependants and beneficiaries who may receive postretirement benefits in the future	13
UNITED STATES | Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit, Lump Sum Buyout Benefits Paid, Current Year	$ 670,000
Settlement loss	0	47,000	0
Estimated future employer contributions in the next fiscal year	$ 0
Discount rate support/source data	Woodward uses a bond portfolio matching analysis based on recently traded, non-callable bonds rated AA or better that have at least $50 million outstanding to determine the benefit obligations at year end.
Accumulated benefit obligation	$ 161,130,000	160,892,000
UNITED STATES | Defined Benefit Pension Plan [Member] | Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit, Lump Sum Buyout Benefits Paid, Expected	$ 0
UNITED STATES | Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate support/source data	Woodward used a bond portfolio matching analysis based on recently traded, non-callable bonds rated AA or better that have at least $50 million outstanding to determine the benefit obligations at year end.
Duarte Plan, Defined Benefit [Member] | Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Settlement loss		47,000
Current defined benefit pension plan liability	$ 0
Foreign Plan [Member] | Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Settlement loss	$ 0	0	$ 0
Discount rate support/source data	Woodward uses a high-quality corporate bond yield curve matched with separate cash flows to develop a single rate to determine the single rate equivalent to settle the entire benefit obligations in each jurisdiction. For the fiscal year ended September 30, 2017 and 2016, the discount rate used to determine periodic service cost and interest cost components of the overall benefit costs was based on spot rates derived from the same high-quality corporate bond yield curve used to determine the September 30, 2017 and 2016, respectively, benefit obligation matched with separate cash flows for each future year. Prior to this change in method, the discount rate used to determine the periodic benefit costs for the year ending September 30, 2015 was based on a single rate equivalent.
Foreign Plan [Member] | Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate support/source data	Woodward uses a high-quality corporate bond yield curve matched with separate cash flows to develop a single rate to determine the single rate equivalent to settle the entire benefit obligations in each jurisdiction. For the fiscal years ended September 30, 2017 and September 30, 2016, the discount rate used to determine periodic service cost and interest cost components of the overall benefit costs was based on spot rates derived from the same high-quality corporate bond yield curve used to determine the September 30, 2016 and 2015, respectively, benefit obligation matched with separate cash flows for each future year.
UNITED KINGDOM | Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions in the next fiscal year	$ 397,000
Accumulated benefit obligation	$ 53,628,000	57,877,000
UNITED KINGDOM | Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Approximate number of retired employees and their covered dependents and beneficiaries currently providing postretirement benefits	6
JAPAN | Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions in the next fiscal year	$ 217,000
Accumulated benefit obligation	$ 10,007,000	$ 10,924,000