Impairments and Other Charges (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Jan. 31, 2020
Tangible Assets And Equipment
Impairment of long-lived assets	$ 147,750
Subtotal	147,750
Goodwill And Intangible Assets:
Goodwill impairments	27,798
Intangible asset impairment	83,624
Subtotal	111,422
Other Charges:
Provision for international activities	15,078
Severance and transaction related costs	2,184
Loss (gain) on debt buyback	(15,700)
Total impairments and other charges	276,434
Debt Instrument, Repurchased Face Amount	1,100,000		$ 952,900
Payment of long-term debt	1,068,405	$ 43,540
Severance and other related costs	2,200
North Slope of Alaska
Tangible Assets And Equipment
Impairment recognized	12,300
U.S. Drilling
Tangible Assets And Equipment
Impairment of long-lived assets	82,400
International Drilling
Tangible Assets And Equipment
Impairment of long-lived assets	30,500
Drilling Solutions
Tangible Assets And Equipment
Impairment of long-lived assets	19,800
Goodwill And Intangible Assets:
Goodwill impairments	11,436
Rig Technologies
Tangible Assets And Equipment
Impairment of long-lived assets	2,800
Goodwill And Intangible Assets:
Goodwill impairments	$ 16,362