Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
Apr. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Jan. 31, 2020
Stockholders' Equity
Cash dividends declared per common share	$ 0.09	$ 0.09	$ 0.08
Cash dividends paid		$ 8,200	$ 7,500
Repurchase common stock authorized amount				$ 75,000
Payments to repurchase shares		$ 14,957
Repurchase of common stock (in shares)		700,901
Average price (per share)		$ 21.32

Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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The cash outflow to reacquire common stock during the period.

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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