Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Apr. 02, 2017	Jul. 01, 2018	Jul. 02, 2017	Jan. 01, 2018
Summary Of Significant Accounting Policies [Line Items]
Revenue recognized in accordance with ASC 606	$ 526,929	$ 696,901		$ 1,014,396	$ 1,153,814
Revenue on leases	3,600			$ 7,900
Standard warranty period				12 months
Deferred revenue and customer advances balance	24,700			$ 46,500
ASU 2014-09
Summary Of Significant Accounting Policies [Line Items]
Revenue recognized in accordance with ASC 606	$ 523,300			$ 1,006,500
ASU 2017-07
Summary Of Significant Accounting Policies [Line Items]
Decrease in income from operations			$ (2,100)		$ (1,700)
Retained Earnings | ASU 2014-09
Summary Of Significant Accounting Policies [Line Items]
Increase (decrease) in adoption of new accounting guidance amount						$ 12,700
Retained Earnings | ASU 2016-01
Summary Of Significant Accounting Policies [Line Items]
Increase (decrease) in adoption of new accounting guidance amount						3,100
Accumulated Other Comprehensive Income (Loss) | ASU 2016-01
Summary Of Significant Accounting Policies [Line Items]
Increase (decrease) in adoption of new accounting guidance amount						$ (3,100)