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Summary of Significant Accounting Policies - Shares Used in Computing Basic and Diluted Earnings Per Share (Details) - shares		1 Months Ended	3 Months Ended
	Aug. 21, 2019	Aug. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Denominator:
Weighted-average common shares outstanding - basic (in shares)			209,439,000	174,413,000
Incremental shares issuable for stock options and awards (in shares)			1,819,000	3,153,000
Weighted-average common shares outstanding - diluted (in shares)			211,258,000	177,566,000
Business Acquisition [Line Items]
Antidilutive shares excluded from calculation of earnings per share (in shares)			3,499,000	30,000
Merger Sub \| Common Stock
Business Acquisition [Line Items]
Shares issued in business acquisition (in shares)	34,612,847	34,613,000