Joint Ventures (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2016	Jan. 04, 2016
Current portion of deferred income recorded in connection with joint venture		$ 6,452			$ 6,552
Noncurrent portion of deferred income recorded in connection with joint venture		236,791			238,187
Income taxes payable		1,374			$ 4,547
Equity interest in earnings of joint venture		684		$ 0
Woodward and General Electric Joint Venture [Member]
Equity Method Investment, Ownership Percentage					50.00%
Cash received from formation of joint venture			$ 250,000
Cash to be received annually from formation of joint venture	$ 4,894
Amount of deferred income recorded in connection with joint venture						$ 250,000
Current portion of deferred income recorded in connection with joint venture		6,452			$ 6,552
Noncurrent portion of deferred income recorded in connection with joint venture		236,791			238,187
Equity interest in earnings of joint venture		684
Cash distributions from joint venture		0
Net investment in joint venture		6,888
Accounts receivable from related party		5,145			5,326
Accounts payable to related party		5,012			$ 3,926
Woodward and General Electric Joint Venture [Member] | Sales [Member]
Amortization of deferred income recognized as an increase to sales		1,496
Sales to related party		15,302
Reduction to sales related to royalties paid to joint venture		$ 5,403