Goodwill and Other Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

The changes in carrying value of goodwill by reportable segment for the nine months ended September 30, 2018 are as follows:

(in millions)	Audio		Precision Devices		Total
Balance at December 31, 2017	$	859.9	$	25.0	$	884.9
Acquisition	—		3.0		3.0
Balance at September 30, 2018	$	859.9	$	28.0	$	887.9

Schedule of Intangible Assets

The gross carrying value and accumulated amortization for each major class of intangible assets are as follows:

	September 30, 2018				December 31, 2017
(in millions)	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
Amortized intangible assets:
Trademarks	$	0.5	$	0.2	$	0.3	$	0.2
Patents	40.8		25.7		40.8		22.2
Customer relationships	10.6		1.7		3.3		0.7
Unpatented technologies	4.4		2.6		2.4		2.2
Other	0.2		—		—		—
Total	56.5		30.2		46.8		25.3
Unamortized intangible assets:
Trademarks	32.0				32.0
Total intangible assets, net	$	58.3			$	53.5

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

Amortization expense for the next five years, based on current intangible balances, is estimated to be as follows:

(in millions)
Q4 2018	$	1.6
2019	6.4
2020	6.4
2021	6.3
2022	1.1