Reportable Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 29, 2015	Mar. 30, 2014	Mar. 29, 2015	Mar. 30, 2014	Sep. 28, 2014
Financial information concerning reportable segments
Revenue	$ 564,763us-gaap_SalesRevenueServicesNet	$ 586,285us-gaap_SalesRevenueServicesNet	$ 1,145,819us-gaap_SalesRevenueServicesNet	$ 1,232,133us-gaap_SalesRevenueServicesNet
Operating income (loss)	30,398us-gaap_OperatingIncomeLoss	46,186us-gaap_OperatingIncomeLoss	67,010us-gaap_OperatingIncomeLoss	89,904us-gaap_OperatingIncomeLoss
Depreciation	5,929us-gaap_Depreciation	6,578us-gaap_Depreciation	12,793us-gaap_Depreciation	13,707us-gaap_Depreciation
Total assets	1,643,947us-gaap_Assets		1,643,947us-gaap_Assets		1,776,404us-gaap_Assets
Inter-segment elimination
Financial information concerning reportable segments
Revenue	(18,939)	(20,871)	(37,654)	(45,699)
Corporate
Financial information concerning reportable segments
Operating income (loss)	(5,145)	16,434	(12,665)	8,799
Depreciation	400	737	1,692	1,491
Corporate
Financial information concerning reportable segments
Total assets	864,208		864,208		929,620
WEI \| Operating segment
Financial information concerning reportable segments
Revenue	223,366	223,977	457,033	453,307
Operating income (loss)	15,787	18,296	37,620	40,521
Depreciation	1,189	1,362	2,422	2,777
Total assets	253,282		253,282		302,877
RME \| Operating segment
Financial information concerning reportable segments
Revenue	342,185	342,897	673,859	702,161
Operating income (loss)	19,751	10,726	45,471	43,985
Depreciation	3,665	3,708	7,344	7,870
Total assets	435,039		435,039		442,911
RCM \| Operating segment
Financial information concerning reportable segments
Revenue	18,151	40,282	52,581	122,364
Operating income (loss)	5	730	(3,416)	(3,401)
Depreciation	675	771	1,335	1,569
Total assets	$ 91,418		$ 91,418		$ 100,996

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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