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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Earnings Per Share - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 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)		$ (500)		$ 1,900	$ (1,400)