Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		$ 771,406	$ 761,920	$ 1,571,046	$ 1,496,114
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		22,260	10,884	48,954	10,827
Earnings (losses) from unconsolidated affiliates			(1)	(5)	1
Investment income (loss)		469	(3,164)	10,146	(2,699)
Interest expense		(51,491)	(60,592)	(103,843)	(121,978)
Remeasurement of net monetary assets charge		102,570	69,620	99,903	76,664
Other, net		(7,899)	(7,981)	(28,068)	(15,026)
Income (loss) from continuing operations before income taxes		(181,403)	(171,937)	(254,980)	(291,979)
ASSETS
Total assets (1)	[1]	7,514,503		7,514,503		$ 7,853,944
U.S. Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		323,402	264,395	643,611	505,397
Canada Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		11,389	17,442	36,704	49,329
International Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		326,905	377,986	664,161	746,831
Drilling Solutions
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		64,583	59,859	130,005	122,507
Rig Technologies
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		72,751	81,321	144,504	145,990
Operating segment
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		22,260	10,884	48,954	10,827
Operating segment | U.S. Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		323,402	264,395	643,611	505,397
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		20,392	(13,107)	45,075	(32,853)
ASSETS
Total assets (1)		2,897,846		2,897,846		2,982,974
Operating segment | Canada Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		11,389	17,442	36,704	49,329
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		(5,537)	(4,608)	(5,596)	(5,200)
ASSETS
Total assets (1)		223,881		223,881		252,817
Operating segment | International Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		326,905	377,986	664,161	746,831
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		(6,884)	24,486	(12,521)	49,022
ASSETS
Total assets (1)		3,104,495		3,104,495		3,320,347
Operating segment | Drilling Solutions
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		64,583	59,859	130,005	122,507
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		13,793	7,546	26,648	16,267
ASSETS
Total assets (1)		251,536		251,536		281,078
Operating segment | Rig Technologies
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		72,751	81,321	144,504	145,990
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		496	(3,433)	(4,652)	(16,409)
ASSETS
Total assets (1)		422,788		422,788		401,044
Other reconciling items (3)
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		27,624	39,083	47,939	73,940
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		(42,172)	$ (41,463)	(82,261)	$ (86,440)
ASSETS
Total assets (1)		$ 613,957		$ 613,957		$ 615,684

[1] The condensed consolidated balance sheet as of June 30, 2019 and December 31, 2018 include assets and liabilities of variable interest entities. See Note 3—Joint Ventures for additional information.