Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Numerator for basic and diluted earnings per share:
Income from continuing operations	$ 111,953	$ 13,737	$ (159,235)	$ 474,730	$ 12,893	$ 86,918	$ 211,898	$ 127,588	$ 441,185	$ 439,297	$ 415,991
Discontinued operations									0	0	(10)
Net income	111,953	13,737	(159,235)	474,730	12,893	86,918	211,898	127,588	441,185	439,297	415,981
Comprehensive income attributable to noncontrolling interests	1,502	986	(2,065)	1,613	1,450	1,659	1,369	1,803	2,036	6,281	6,514
Net income attributable to common stockholders	$ 110,451	$ 12,751	$ (157,170)	$ 473,117	$ 11,443	$ 85,259	$ 210,529	$ 125,785	$ 439,149	$ 433,016	$ 409,467
Denominator:
Denominator for basic earnings per share - weighted average shares (in shares)									373,368	365,977	356,265
Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants									0	391	174
Stock options (in shares)									171	527	331
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares									2,964	2,991	2,531
Denominator for diluted earnings per share - adjusted weighted average shares (in shares)									376,503	369,886	359,301
Basic earnings per share:
Income from continuing operations (USD per share)	$ 0.30	$ 0.04	$ (0.43)	$ 1.27	$ 0.03	$ 0.23	$ 0.59	$ 0.36	$ 1.18	$ 1.20	$ 1.17
Net income attributable to common stockholders (USD per share)	0.29	0.03	(0.42)	1.27	0.03	0.23	0.58	0.35	1.18	1.18	1.15
Diluted earnings per share:
Income from continuing operations (USD per share)	0.30	0.04	(0.43)	1.26	0.03	0.23	0.58	0.35	1.17	1.19	1.16
Net income attributable to common stockholders (USD per share)	$ 0.29	$ 0.03	$ (0.42)	$ 1.26	$ 0.03	$ 0.23	$ 0.58	$ 0.35	$ 1.17	$ 1.17	$ 1.14
Anti-dilutive options outstanding (in shares)									4,000	1,100	3,500