Goodwill and Intangible Assets (Tables)

9 Months Ended

Oct. 28, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Changes in Carrying Amounts of Goodwill

Changes in the carrying amount of goodwill by applicable reporting unit were as follows:

(in thousands)	Signal Integrity		Wireless and Sensing		Protection		Total
Balance at January 28, 2018	$	274,085	$	67,812	$	—	$	341,897
Additions	—		8,500		4,778		13,278
Balance at October 28, 2018	$	274,085	$	76,312	$	4,778	$	355,175

Schedule of Finite-lived Intangible Assets Acquired

The following table sets forth the Company’s finite-lived intangible assets resulting from business acquisitions, which continue to be amortized:

		October 28, 2018							January 28, 2018
(in thousands)	Estimated Useful Life	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Core technologies	5-8 years	$	164,930	$	(131,250	)	$	33,680	$	164,930	$	(115,628	)	$	49,302
Customer relationships	3-10 years	34,031		(29,725		)	4,306		34,031		(25,426		)	8,605
Total finite-lived intangible assets		$	198,961	$	(160,975	)	$	37,986	$	198,961	$	(141,054	)	$	57,907

Amortization expenses recorded in the Statements of Income for each period were as follows:

	Three Months Ended				Nine Months Ended
(in thousands)	October 28, 2018		October 29, 2017		October 28, 2018		October 29, 2017
Core technologies	$	5,047	$	6,020	$	15,622	$	16,669
Customer relationships	1,433		1,433		4,299		3,745
Total amortization expense	$	6,480	$	7,453	$	19,921	$	20,414

Schedule of Indefinite-Lived Intangible Assets

The following table sets forth the Company’s indefinite-lived intangible assets resulting from additions to in-process research and development:

(in thousands)	Net Carrying Value
Value at January 28, 2018	$	2,300
In-process research and development through acquisitions	—
Value at October 28, 2018	$	2,300