Business Combinations - Unaudited Pro Forma Results (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Business Combinations [Abstract]
Total revenues	$ 728,163	$ 609,781	$ 1,546,249	$ 1,318,896
Income before income taxes	186,582	131,738	426,711	339,204
Net income	$ 139,494	$ 98,532	$ 339,986	$ 252,571
Net income per share:
Basic	$ 0.50	$ 0.35	$ 1.20	$ 0.89
Diluted	$ 0.49	$ 0.35	$ 1.20	$ 0.89
Weighted average number of shares outstanding:
Basic	275,694	273,100	275,644	272,938
Diluted	276,877	274,362	276,914	274,519

Business acquisitions proforma income loss before income taxes.

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Per basic share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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Per diluted share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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The weighted average number of shares or units and dilutive common stock or unit equivalents outstanding in the calculation of proforma diluted earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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The weighted average number of shares (units) outstanding in the calculation of pro forma basic earnings per share (earnings per unit), which is commonly presented in initial public offerings based on the terms of the offering.

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