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					9 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Mar. 13, 2020	Nov. 30, 2014
Dividends Payable [Line Items]
Cash dividends declared per common share (usd per share)		$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.24	$ 0.24
Payments of common stock dividends		$ 4,800,000	$ 4,900,000	$ 4,800,000	$ 4,900,000	$ 14,500,000	$ 14,500,000
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased		7,227				498,217	48,409
Treasury stock purchases		$ 200,000				$ 13,700,000	$ 1,000,000.0
Subsequent Event
Dividends Payable [Line Items]
Cash dividends declared per common share (usd per share)	$ 0.08
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