Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Oct. 01, 2018
Contract Assets and Liabilities
Contract Assets	$ 320,277		$ 272,210
Contract Liabilities	69,713		$ 70,128
Increase in contract asset	48,100
Impairment losses related to contract assets	0	$ 0
Decrease in contract liabilities	400
Revenue recognized included in contract liability at beginning of quarter	$ 20,700

Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

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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.

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

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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 of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

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