Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Balance Type:	debit
Period Type:	duration

Earnings Per Share - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Shares repurchased					0.8
Shares repurchased at cost			$ 7,500	$ 14,069	$ 7,500
Performance Restricted Stock Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Mark-to-market adjustment	$ (300)	$ (1,400)			$ 1,600	$ (2,800)