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Commitments and Contingencies (Details) - USD ($)		1 Months Ended	3 Months Ended
Commitments and Contingencies (Details) - USD ($)	Mar. 28, 2019	Aug. 31, 2017	Jun. 28, 2019	Sep. 28, 2018	Sep. 28, 2012
UGL Infrastructure Pty Limited
Loss Contingencies [Line Items]
Percentage of ownership interest in joint venture					50.00%
Nui Phao Mining Company
Loss Contingencies [Line Items]
Damages sought	$ 70,000,000.0
Damages awarded	$ 95,000,000.0		$ 147,000,000.0
General Electric and GE Electrical International Inc \| Pending Litigation \| Minimum
Loss Contingencies [Line Items]
Damages sought		$ 530,000,000.0
JKC Australia LNG Pty Limited \| Pending Litigation
Loss Contingencies [Line Items]
Damages sought		$ 1,700,000,000
Line of Credit
Loss Contingencies [Line Items]
Short-term debt			359,000,000.0	$ 446,600,000
Surety Bond
Loss Contingencies [Line Items]
Short-term debt			$ 1,160,000,000	$ 870,300,000