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Mergers and Acquisitions - Acquisition Narrative (Details) |  | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Oct. 02, 2017 employee | Apr. 02, 2017 USD ($) employee | Mar. 27, 2016 USD ($) employee | Jun. 28, 2015 USD ($) | Sep. 27, 2015 USD ($) | Oct. 01, 2017 USD ($) | Oct. 02, 2016 USD ($)
Business acquisition |  |  |  |  |  |  |
Contingent earn-out liability |  |  |  |  | $ 0 | $ 2,400,000 |
Aggregate maximum of contingent consideration |  |  |  |  |  | $ 8,900,000 |
CEG |  |  |  |  |  |  |
Business acquisition |  |  |  |  |  |  |
Aggregate fair value of purchase prices |  |  |  |  | 15,900,000 |  |
Cash paid to the sellers |  |  |  |  | 11,800,000 |  |
Contingent earn-out liability |  | $ 1,800,000 |  | $ 4,100,000 | 4,100,000 |  | $ 3,900,000
Aggregate maximum of contingent consideration |  |  |  | $ 9,800,000 | $ 9,800,000 |  |
Earn-out period |  |  |  | 3 years |  |  |
Coffey |  |  |  |  |  |  |
Business acquisition |  |  |  |  |  |  |
Aggregate fair value of purchase prices |  |  | $ 76,100,000 |  |  |  |
Number of employees | employee |  |  | 3,300 |  |  |  |
Assumed debt |  |  | $ 65,100,000 |  |  |  |
Secured bank debt assumed |  |  | 37,100,000 |  |  |  |
Unsecured corporate bonds assumed |  |  | 28,000,000 |  |  |  |
INDUS |  |  |  |  |  |  |
Business acquisition |  |  |  |  |  |  |
Aggregate fair value of purchase prices |  |  | 18,700,000 |  |  |  |
Cash paid to the sellers |  |  | 14,000,000 |  |  |  |
Contingent earn-out liability |  | 0 | 4,700,000 |  |  |  | $ 4,900,000
Aggregate maximum of contingent consideration |  |  | $ 8,000,000 |  |  |  |
Earn-out period |  |  | 2 years |  |  |  |
ELA |  |  |  |  |  |  |
Business acquisition |  |  |  |  |  |  |
Aggregate fair value of purchase prices |  | 9,900,000 |  |  |  |  |
Cash paid to the sellers |  | 8,300,000 |  |  |  |  |
Contingent earn-out liability |  | 1,600,000 |  |  |  |  |
Aggregate maximum of contingent consideration |  | $ 1,700,000 |  |  |  |  |
Number of employees | employee |  | 160 |  |  |  |  |
Earn-out period |  | 2 years |  |  |  |  |
Glumac | Subsequent Event |  |  |  |  |  |  |
Business acquisition |  |  |  |  |  |  |
Number of employees | employee | 300 |  |  |  |  |  |

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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
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