The cash outflow for cost incurred directly with the issuance of an equity security.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Stockholders' Equity (Public Offering) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands			3 Months Ended	12 Months Ended
	Sep. 05, 2018	Aug. 07, 2018	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsidiary, Sale of Stock [Line Items]
Shares issued (in shares)			12,300
Payments made for costs related to common stock issuances				$ 0	$ 0	$ 329
Public Offering
Subsidiary, Sale of Stock [Line Items]
Shares Issued (in shares)		50,875
Gross proceeds (usd per share)		$ 7.78
Gross Proceeds		$ 395,807
Shares issued (in shares)	875
Payments made for costs related to common stock issuances	$ 6,400