Joint Ventures (Details) (USD $)	3 Months Ended	6 Months Ended
Mar. 29, 2015	Mar. 30, 2014	Mar. 29, 2015	Mar. 30, 2014	Sep. 28, 2014
Aggregate revenue of consolidated joint ventures	$ 564,763,000us-gaap_SalesRevenueServicesNet	$ 586,285,000us-gaap_SalesRevenueServicesNet	$ 1,145,819,000us-gaap_SalesRevenueServicesNet	$ 1,232,133,000us-gaap_SalesRevenueServicesNet
Unconsolidated Joint Ventures
Equity in earnings from unconsolidated joint ventures	1,200,000	800,000	1,842,000	1,492,000
Carrying value of assets of unconsolidated joint ventures	17,600,000		17,600,000		20,100,000
Carrying value of liabilities of unconsolidated joint ventures	15,400,000		15,400,000		18,000,000
Consolidated Joint Ventures
Aggregate revenue of consolidated joint ventures	1,600,000	3,500,000	3,800,000	6,200,000
Cash and cash equivalents of consolidated joint ventures	$ 1,300,000		$ 1,300,000		$ 1,400,000

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

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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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Carrying amount of the liabilities 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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