Goodwill and Intangible Assets (Tables)
 3 Months Ended
Mar. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]  
Summary of Goodwill by Reportable Segment
The following table summarizes goodwill by reportable segment (in millions): 
 
 
As of March 30, 2018
 
As of December 31, 2017
 
 
Goodwill
 
Accumulated Impairment Losses
 
Carrying Value
 
Goodwill
 
Accumulated Impairment Losses
 
Carrying Value
Reportable Segment:
 
 
 
 
 
 
 
 
 
 
 
 
Power Solutions Group
 
$
432.2

 
$
(28.6
)
 
$
403.6

 
$
432.2

 
$
(28.6
)
 
$
403.6

Analog Solutions Group
 
836.7

 
(418.9
)
 
417.8

 
836.7

 
(418.9
)
 
417.8

Image Sensor Group
 
95.5

 
—

 
95.5

 
95.5

 
—

 
95.5

 
 
$
1,364.4

 
$
(447.5
)
 
$
916.9

 
$
1,364.4

 
$
(447.5
)
 
$
916.9
Summary of Intangible Assets, Net
Intangible assets, net, were as follows (in millions):
 
As of March 30, 2018
 
Original
Cost
 
Accumulated
Amortization
 
Accumulated Impairment Losses
 
Carrying
Value
Intellectual property
$
13.9

 
$
(12.0
)
 
$
(0.4
)
 
$
1.5

Customer relationships
555.9

 
(336.1
)
 
(20.1
)
 
199.7

Patents
43.7

 
(27.1
)
 
(13.7
)
 
2.9

Developed technology
657.6

 
(297.2
)
 
(2.6
)
 
357.8

Trademarks
17.2

 
(12.6
)
 
(1.1
)
 
3.5

Backlog
3.3

 
(3.3
)
 
—

 
—

Favorable Leases
1.7

 
(1.7
)
 
—

 
—

IPRD
54.5

 
—

 
(19.0
)
 
35.5

Total intangibles
$
1,347.8

 
$
(690.0
)
 
$
(56.9
)
 
$
600.9


 
As of December 31, 2017
 
Original
Cost
 
Accumulated
Amortization
 
Accumulated Impairment Losses
 
Carrying
Value
Intellectual property
$
13.9

 
$
(11.8
)
 
$
(0.4
)
 
$
1.7

Customer relationships
555.9

 
(328.5
)
 
(20.1
)
 
207.3

Patents
43.7

 
(26.8
)
 
(13.7
)
 
3.2

Developed technology
657.6

 
(278.2
)
 
(2.6
)
 
376.8

Trademarks
17.2

 
(12.4
)
 
(1.1
)
 
3.7

Backlog
3.3

 
(3.3
)
 
—

 
—

Favorable Leases
1.7

 
(1.6
)
 
—

 
0.1

IPRD
54.5

 
—

 
(19.0
)
 
35.5

Total intangibles
$
1,347.8

 
$
(662.6
)
 
$
(56.9
)
 
$
628.3
Summary of Amortization Expense
Amortization expense for intangible assets, with the exception of the $35.5 million of IPRD assets that will be amortized once the corresponding projects have been completed, is expected to be as follows for remainder of 2018, each of the next four years, and thereafter (in millions): 
Period
 
Amortization Expense
Remainder of 2018
 
$
81.7

2019
 
99.8

2020
 
84.9

2021
 
70.0

2022
 
57.9

Thereafter
 
171.1

Total amortization expense
 
$
565.4