Property, Plant and Equipment

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Property, plant and equipment consist of the following:



	December 31,
	2017			2016
	(In thousands)
Land	$	224,894		$	240,719
Land use rights	26,845			26,845
Buildings and improvements	1,384,846			1,362,007
Machinery and equipment	4,938,291			4,483,523
Software and computer equipment	200,500			205,969
Furniture, fixtures and other equipment	15,722			21,313
Construction in progress	104,910			87,037
Total property, plant and equipment	6,896,008			6,427,413
Less accumulated depreciation and amortization	(4,200,943		)	(3,862,765		)
Total property, plant and equipment, net	$	2,695,065		$	2,564,648

The following table summarizes our depreciation expense:



	For the Year Ended December 31,
	2017		2016		2015
	(In thousands)
Depreciation expense	$	580,172	$	552,989	$	492,458

We had $46.9 million and $44.8 million of costs for our factory and research and development facility in Korea ("K5") in construction in progress as of December 31, 2017 and 2016, respectively.

As part of our plan to consolidate factory operations in Korea, we sold the land and buildings comprising our K1 factory in May 2017 for $142.4 million. We received 10% of the sale price at signing in November 2016 and the balance at closing, at which time we recognized a pre-tax gain of $108.1 million.