Property and Equipment

12 Months Ended

Dec. 31, 2018

Property Plant And Equipment [Abstract]

4. Property and Equipment

Property and equipment consist of the following (in thousands):

	Estimated Useful		December 31,
	Life (Years)		2018			2017
Land		—	$	875		$	875
Buildings	39-40			17,389			17,389
Building improvements	5-40			34,967			34,957
Machinery and equipment	3-15			61,217			62,681
Furniture, fixtures and office equipment	5-10			2,954			3,556
Computer equipment and software		3		8,355			8,416
Construction in progress		—		342			—
				126,099			127,874
Less accumulated depreciation				(100,497	)		(100,952	)
Total property and equipment, net			$	25,602		$	26,922

Depreciation expense related to property and equipment for the years ended December 31, 2018, 2017 and 2016, was $1.7 million, $1.8 million and $2.4 million, respectively. The Company disposed of $2.1 million of furniture and fixtures, manufacturing equipment and laboratory equipment as it was no longer in service. The net book value was de minimis.

On January 6, 2017, the Company and Rexford Industrial Realty, L.P. (“Rexford”) entered into an Agreement of Purchase and Sale and Joint Escrow Instructions (the “Purchase Agreement”), pursuant to which the Company agreed to sell and Rexford agreed to purchase certain parcels of real estate owned by the Company in Valencia, California and certain related improvements, personal property, equipment, supplies and fixtures (collectively, the “Property”) for $17.3 million. This asset in the amount of $16.7 million was classified as held for sale as of December 31, 2016. The sale and purchase of the Property for $17.3 million pursuant to the terms of the Purchase Agreement, as amended, was completed on February 17, 2017. Net proceeds were $16.7 million after deducting broker’s commission and other fees of approximately $0.6 million paid by the Company. Net proceeds received approximated the carrying value of the asset held for sale.