Property, Plant and Equipment

12 Months Ended

Dec. 31, 2021

Property Plant And Equipment [Abstract]

Property, Plant and Equipment

7. Property, Plant and Equipment

Property, plant and equipment consisted of the following (in millions):

	As of December 31,
	2021			2020
Land	$	27.3		$	27.7
Building and equipment		2,311.4			2,197.8
Capitalized software costs		496.7			455.8
Instruments		3,776.2			3,518.3
Construction in progress		124.0			125.3
		6,735.6			6,324.9
Accumulated depreciation		(4,719.1	)		(4,277.2	)
Property, plant and equipment, net	$	2,016.5		$	2,047.7

Depreciation expense was $451.7 million, $435.1 million and $421.8 million for the years ended December 31, 2021, 2020 and 2019, respectively.

We had $11.6 million and $24.4 million of property, plant and equipment included in accounts payable as of December 31, 2021 and 2020, respectively.