Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The amount of net income (loss) reported by an equity method investment of the entity.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

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Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

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Joint Ventures and VIE's (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Joint Ventures and VIE's (Details) - USD ($) $ in Thousands	Mar. 27, 2020	Mar. 29, 2019	Mar. 27, 2020	Mar. 29, 2019	Sep. 27, 2019
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Consolidated assets	$ 13,134,613		$ 13,134,613		$ 11,462,711
Amount by which equity method investments exceeded share of venture net assets	70,300		70,300
Consolidated Joint Venture \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Consolidated assets	237,300		237,300		192,600
Consolidated Joint Venture \| VIE Primary beneficiary, aggregate disclosure \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
Consolidated liabilities	134,300		134,300		138,500
Unconsolidated Joint Venture \| VIE not primary beneficiary, aggregate disclosure
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
VIE unconsolidated assets	96,000		96,000		61,100
VIE unconsolidated liabilities	87,500		87,500		63,700
Accounts receivable from unconsolidated joint ventures accounted for under the equity method	7,400		7,400		19,500
Unconsolidated Joint Venture \| VIE, not primary beneficiary
Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets and Liabilities, Net [Abstract]
VIE unconsolidated assets	166,900		166,900		$ 157,900
Income from equity method joint ventures	$ 18,800	$ 12,400	$ 36,000	$ 25,900