Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Cumulative effect of new accounting pronouncement
Cumulative effect of accounting changes		$ (9,308)
Trade accounts receivable and contract assets, net	$ 187,919		$ 196,629
Other current assets, net	189,887		179,531
Other investments, net	298,147		325,405
Other non-current assets, net	339,640		334,841
Total assets	6,959,621		7,154,298
Deferred tax liabilities, net	339,006		351,692
Accumulated earnings	569,446		632,809
Non-controlling interests	58,229		75,748
Total stockholders’ equity	3,605,575		3,745,553	$ 4,179,536	$ 4,155,474
Total liabilities and stockholders’ equity	6,959,621		7,154,298
Accumulated Earnings (Losses)
Cumulative effect of new accounting pronouncement
Cumulative effect of accounting changes		(9,068)
Total stockholders’ equity	$ 569,446		$ 632,809	$ 709,928	$ 694,129
Adoption of ASC 326 Increase (Decrease)
Cumulative effect of new accounting pronouncement
Trade accounts receivable and contract assets, net		(13,672)
Other current assets, net		6,723
Other investments, net		(7,381)
Other non-current assets, net		4,050
Total assets		(10,280)
Deferred tax liabilities, net		(972)
Accumulated earnings		(9,068)
Non-controlling interests		(240)
Total stockholders’ equity		(9,308)
Total liabilities and stockholders’ equity		(10,280)
Balance at January 1, 2020
Cumulative effect of new accounting pronouncement
Trade accounts receivable and contract assets, net		182,957
Other current assets, net		186,254
Other investments, net		318,024
Other non-current assets, net		338,891
Total assets		7,144,018
Deferred tax liabilities, net		350,720
Accumulated earnings		623,741
Non-controlling interests		75,508
Total stockholders’ equity		3,736,245
Total liabilities and stockholders’ equity		7,144,018
Accounting Standards Update 2016-13
Cumulative effect of new accounting pronouncement
Accumulated earnings		2,900
Accounting Standards Update 2016-13 | Accumulated Earnings (Losses)
Cumulative effect of new accounting pronouncement
Cumulative effect of accounting changes		$ (9,100)