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Revenue Recognition Net Unfavorable Operating Income Adjustments

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Cumulative provision for contract losses not offset against related costs accumulated on the balance sheet.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Revenue Recognition - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Apr. 01, 2018	Mar. 31, 2019	Apr. 01, 2018	Oct. 01, 2018	Sep. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Decrease to retained earnings upon adoption of new accounting guidance	$ (1,026,836)		$ (1,026,836)			$ (944,965)
Increase to contract assets due to adoption of new accounting guidance	(157,918)		(157,918)			(142,882)
Contracts liabilities	(154,609)		(154,609)			(143,270)
Increase to deferred tax assets due to adoption of new accounting guidance	30,581		30,581			8,607
Contract liability revenue recognized during the period			74,200
Liabilities for anticipated losses	11,700		11,700			$ 13,600
Estimated cost to complete the related contracts	11,700		11,700
Impact of the Adoption of ASC 606 \| Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Decrease to retained earnings upon adoption of new accounting guidance					$ 2,800
Increase to contract assets due to adoption of new accounting guidance					5,000
Contracts liabilities					1,100
Increase to deferred tax assets due to adoption of new accounting guidance					$ 1,100
CIG
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unfavorable operating income adjustments	$ 2,800	$ 700	$ 3,200	$ 1,400