Drilling and Other Property and Equipment

9 Months Ended

Sep. 30, 2020

Property Plant And Equipment [Abstract]

Drilling and Other Property and Equipment

8. Drilling and Other Property and Equipment

Cost and accumulated depreciation of drilling and other property and equipment are summarized as follows (in thousands):

	September 30,			December 31,
	2020			2019
Drilling rigs and equipment	$	7,026,827		$	8,004,489
Land and buildings		64,076			64,267
Office equipment and other		92,216			92,289
Cost		7,183,119			8,161,045
Less: accumulated depreciation		(2,940,013	)		(3,008,217	)
Drilling and other property and equipment, net	$	4,243,106		$	5,152,828

During the first quarter of 2020, we recorded an aggregate impairment charge of $774.0 million, to write down four of our drilling rigs with indicators of impairment to their estimated fair values. See Notes 4 and 7.  In the second quarter of 2020, we transferred the net book value of the Ocean America and Ocean Rover, two previously impaired semisubmersible rigs, to “Assets held for sale” in our unaudited Condensed Consolidated Balance Sheets at September 30, 2020.