Earnings Per Share - Schedule of Calculation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Earnings Per Common Share - Basic:
Net income	$ 36,425	$ 100,131
Preferred stock dividends	(3,598)	(3,598)
Dividends and undistributed earnings allocated to unvested restricted shares	(367)	(933)
Earnings allocated to common shareholders	$ 32,460	$ 95,600
Weighted average common shares outstanding (in shares)	51,979	54,177
Earnings per common share - basic (in usd per share)	$ 0.62	$ 1.76
Earnings Per Common Share - Diluted:
Earnings allocated to common shareholders - basic	$ 32,460	$ 95,600
Adjustment for undistributed earnings allocated to unvested restricted shares	(3)	(42)
Earnings allocated to common shareholders - diluted	$ 32,457	$ 95,558
Weighted average common shares outstanding (in shares)	51,979	54,177
Dilutive potential common shares (in shares)	217	362
Weighted average common shares outstanding - diluted (in shares)	52,196	54,539
Earnings per common share - diluted (in usd per share)	$ 0.62	$ 1.75

Dilutive potential common shares stock options.

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Distributed and undistributed earnings reallocated to unvested restricted stock.

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The total amount of net income in the current period allocated to common shareholders under the two-class method of calculating earnings per share on a basic per share basis.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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