CAPITAL ASSETS

Property and Equipment

Property and equipment are as follows:



(in thousands)	July 1, 2017			October 1, 2016
Land and improvements	$	2,866		$	2,865
Buildings and improvements	59,764			59,350
Machinery and equipment	197,715			189,406
Assets held under capital leases	2,452			—
Total property and equipment, gross	262,797			251,621

Less: Accumulated depreciation	(161,714		)	(150,832		)
Total property and equipment, net	$	101,083		$	100,789

Assets held under capital leases, consisting of machinery and equipment, are recorded at the present value of minimum lease payments and are amortized on a straight-line basis over the estimated life of the asset or the lease term. Amortization of assets held as capital leases is included in depreciation expense in the Consolidated Statements of Income.

Goodwill

Changes to the carrying amount of goodwill are as follows:



(in thousands)	Test			Sensors			Total
Balance, October 1, 2016	$	25,022		$	344,678		$	369,700
Adjustment related to finalization of purchase accounting¹	—			(64		)	(64		)
Currency translation	(252		)	15			(237		)
Balance, July 1, 2017	$	24,770		$	344,629		$	369,399


¹	Goodwill from our acquisition of PCB Group, Inc. and its wholly owned subsidiaries (PCB) was finalized in the third quarter of fiscal year 2017. See Note 17 for additional information related to our acquisition of PCB.

Intangible Assets

Intangible assets are as follows:



	July 1, 2017
(in thousands)	Gross Carrying Amount		Accumulated Amortization			Net Carrying Value		Weighted Average Useful Life (in Years)
Software development costs	$	25,348	$	(15,607	)	$	9,741	6.0
Technology and patents	46,500		(8,508		)	37,992		14.9
Trademarks and trade names	6,807		(2,305		)	4,502		25.5
Customer lists	156,993		(10,856		)	146,137		15.8
Land-use rights	2,338		(416		)	1,922		26.2
Trade names	57,500		—			57,500		Indefinite
Total intangible assets	$	295,486	$	(37,692	)	$	257,794	15.0



	October 1, 2016
(in thousands)	Gross Carrying Amount		Accumulated Amortization			Net Carrying Value		Weighted Average Useful Life (in Years)
Software development costs	$	23,184	$	(14,938	)	$	8,246	6.0
Technology and patents	46,672		(6,360		)	40,312		14.9
Trademarks and trade names	6,903		(1,911		)	4,992		25.5
Customer lists	156,987		(3,372		)	153,615		15.8
Land-use rights	2,369		(245		)	2,124		26.3
Trade names	57,500		—			57,500		Indefinite
Total intangible assets	$	293,615	$	(26,826	)	$	266,789	15.1

Amortization expense recognized during the three months ended July 1, 2017 and July 2, 2016 was $3,656 and $596, respectively. Amortization expense recognized during the nine months ended July 1, 2017 and July 2, 2016 was $10,984 and $1,793, respectively.

The estimated future amortization expense related to amortizable intangible assets is as follows:



(in thousands)	Amortization Expense
Remainder of 2017	$	3,641
2018	13,701
2019	13,576
2020	13,295
2021	13,295
2022	13,112
Thereafter	129,674

Future amortization amounts presented above are estimates. Actual future amortization expense may be different due to future acquisitions, impairments, changes in amortization periods or other factors.