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Stockholders' Equity - Narrative (Details) - USD ($)		3 Months Ended		6 Months Ended	9 Months Ended		26 Months Ended
	Oct. 23, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Jan. 24, 2020	Apr. 23, 2018
Class of Stock [Line Items]
Shares withheld for tax withholding and exercise of options (in shares)					9,214	7,795
Amount of shares withheld for tax withholding and exercise of options					$ 369,000	$ 326,000
Shares withheld for tax withholding and exercise of options, weighted average price (in usd per share)					$ 40.01	$ 41.84
Share repurchase program, amount approved to repurchase								$ 25,000,000.0	$ 25,000,000.0
Stock repurchased, net of commissions			$ 2,726,000		$ 3,230,000	$ 13,170,000	$ 25,200,000
Subsequent event
Class of Stock [Line Items]
Dividends declared per common share (in usd per share)	$ 0.23
Common Stock
Class of Stock [Line Items]
Stock repurchased, net of commissions (in shares)		0	65,127	0	92,664	313,651	619,881
Stock repurchased, net of commissions			$ 2,726,000		$ 3,230,000	$ 13,170,000
Performance-based stock awards
Class of Stock [Line Items]
Vesting period of performance-based stock awards					3 years
Performance-based stock awards | Minimum
Class of Stock [Line Items]
Vesting percentage of performance-based awards					0.00%
Performance-based stock awards | Maximum
Class of Stock [Line Items]
Vesting percentage of performance-based awards					200.00%

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