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

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The cash outflow to reacquire common stock during the period.

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Stockholders' Equity - Additional Information (Details) - USD ($)	3 Months Ended				6 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Mar. 13, 2020	Nov. 30, 2014
Dividends Payable [Line Items]
Cash dividends declared per common share (usd per share)		$ 0.09	$ 0.09	$ 0.08	$ 0.18	$ 0.16
Cash dividends paid to stockholders		$ 5,500,000	$ 5,500,000	$ 4,900,000	$ 11,000,000.0	$ 9,700,000
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased		5,000			5,000	490,990
Treasury stock purchases		$ 200,000			$ 200,000	$ 13,500,000
Subsequent Event
Dividends Payable [Line Items]
Cash dividends declared per common share (usd per share)	$ 0.09
November 2014 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount								$ 75,000,000.0
March 2020 Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount							$ 75,000,000.0