Segment Information - By Geographic Area (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) customer	Dec. 31, 2018 USD ($) customer	Dec. 31, 2017 USD ($) customer
Financial information with respect to entity's operations by geographic area
Operating revenues	$ 714,261	$ 758,076	$ 771,406	$ 799,640	$ 782,080	$ 779,425	$ 761,920	$ 734,194	$ 3,043,383	$ 3,057,619	$ 2,564,285
Property, Plant and Equipment, Net	4,930,549				5,467,870				4,930,549	5,467,870	6,109,565
Goodwill	28,380				183,914				$ 28,380	$ 183,914	$ 173,226
Sales Revenue | One customer
Financial information with respect to entity's operations by geographic area
Number of customers | customer									1	1	1
Sales Revenue | Customer Concentration Risk | One customer
Financial information with respect to entity's operations by geographic area
Percentage									22.00%	24.00%	29.00%
U.S. Drilling
Financial information with respect to entity's operations by geographic area
Operating revenues									$ 1,554,442	$ 1,347,448	$ 973,464
Property, Plant and Equipment, Net	2,470,579				2,892,910				2,470,579	2,892,910	3,163,425
Goodwill	13,430				65,633				13,430	65,633	54,198
Outside the U.S
Financial information with respect to entity's operations by geographic area
Operating revenues									1,488,941	1,710,171	1,590,821
Property, Plant and Equipment, Net	2,459,970				2,574,960				2,459,970	2,574,960	2,946,140
Goodwill	$ 14,950				$ 118,281				14,950	118,281	119,028
Saudi Arabia
Financial information with respect to entity's operations by geographic area
Operating revenues									$ 696,400	$ 764,500	$ 727,700