Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		$ 758,076	$ 779,425	$ 2,329,122	$ 2,275,539
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		24,696	31,728	73,650	42,555
Earnings (losses) from unconsolidated affiliates				(5)	1
Investment income (loss)		(1,437)	(1,342)	8,709	(4,041)
Interest expense		(51,291)	(51,415)	(155,134)	(173,393)
Remeasurement of net monetary assets charge		3,629	13,770	106,007	90,434
Other, net		(5,005)	(9,137)	(30,598)	(24,163)
Income (loss) from continuing operations before income taxes		(75,885)	(83,221)	(330,865)	(375,200)
ASSETS
Total assets (1)	[1]	7,273,497		7,273,497		$ 7,853,944
U.S. Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		307,808	273,996	951,419	779,393
Canada Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		12,191	26,645	48,895	75,974
International Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		328,278	377,125	992,439	1,123,956
Drilling Solutions
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		62,286	60,923	192,291	183,430
Rig Technologies
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		63,106	63,641	207,610	209,631
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		24,696	31,728	73,650	42,555
Operating segment | U.S. Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		307,808	273,996	951,419	779,393
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		12,427	2,578	57,502	(30,275)
ASSETS
Total assets (1)		2,521,098		2,521,098		2,982,974
Operating segment | Canada Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		12,191	26,645	48,895	75,974
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		(5,701)	(1,895)	(11,297)	(7,095)
ASSETS
Total assets (1)		215,813		215,813		252,817
Operating segment | International Drilling
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		328,278	377,125	992,439	1,123,956
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		2,466	25,680	(10,055)	74,702
ASSETS
Total assets (1)		3,084,525		3,084,525		3,320,347
Operating segment | Drilling Solutions
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		62,286	60,923	192,291	183,430
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		16,145	9,506	42,793	25,773
ASSETS
Total assets (1)		222,605		222,605		281,078
Operating segment | Rig Technologies
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		63,106	63,641	207,610	209,631
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		(641)	(4,141)	(5,293)	(20,550)
ASSETS
Total assets (1)		411,831		411,831		401,044
Other reconciling items (3)
Operating revenues and earnings (losses) from unconsolidated affiliates:
Operating revenues		15,593	22,905	63,532	96,845
Reconciliation of segment adjusted operating income (loss) to net income (loss) from continuing operations before income taxes:
Adjusted income (loss) derived from operating activities		(39,219)	$ (39,285)	(121,480)	$ (125,725)
ASSETS
Total assets (1)		$ 817,625		$ 817,625		$ 615,684

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