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, 2019	Mar. 31, 2019	Jun. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock repurchase program authorized amount					$ 100,000
Shares repurchased		1.2
Shares repurchased at cost		$ 14,100	$ 14,069
Performance Restricted Stock Units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Mark-to-market adjustment	$ 1,400			$ 2,800