Note 6. Financial Statement Components

The following tables provide details of selected financial statement components as of the following dates (in thousands):

	At
	April 1, 2017			December 31, 2016
Inventories:
Raw materials and sub-assemblies	$	23,185		$	23,506
Work in process		14,383			10,347
Finished goods		3,976			4,984
Inventories		41,544			38,837
Inventories-delivered systems		3,280			2,457
Total inventories	$	44,824		$	41,294

Property, plant and equipment, net:⁽¹⁾
Land	$	15,571		$	15,568
Building and improvements		20,566			20,532
Machinery and equipment		37,122			35,659
Furniture and fixtures		2,419			2,282
Software		9,776			9,756
Capital in progress		2,036			2,748
Total property, plant and equipment, gross		87,490			86,545
Accumulated depreciation and amortization		(44,314	)		(42,319	)
Total property, plant and equipment, net	$	43,176		$	44,226
⁽¹⁾Total depreciation and amortization expense was $1.8 million and $1.7 million for the three months ended April 1, 2017 and March 26, 2016, respectively.
Other Current Liabilities:
Accrued warranty	$	4,244		$	3,838
Customer deposits		—			581
Retrofit liability		984			432
Accrued professional services		570			424
Accrued royalties		60			1,233
Other		1,435			1,539
Total other current liabilities	$	7,293		$	8,047

Components of Accumulated Other Comprehensive Income (Loss)

	Years Ended
	Foreign Currency Translations			Defined Benefit Pension Plans			Unrealized Income (Loss) on Investment			Accumulated Other Comprehensive Income
Balance as of December 31, 2016	$	(5,817	)	$	(227	)	$	(2	)	$	(6,046	)
Current period change		1,945			—			(9	)		1,936
Balance as of April 1, 2017	$	(3,872	)	$	(227	)	$	(11	)	$	(4,110	)

The items above, except for unrealized income (loss) on investment, did not impact the Company’s income tax provision. The amounts reclassified from each component of accumulated other comprehensive income into income statement line items were insignificant.