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Stockholders' Equity - Narrative (Details)			3 Months Ended			9 Months Ended		14 Months Ended
	Oct. 18, 2019 $ / shares	Nov. 27, 2018	Sep. 30, 2019 USD ($) shares	Sep. 30, 2018 USD ($) shares	Mar. 31, 2018 USD ($)	Sep. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2018 USD ($) $ / shares shares	Jun. 30, 2019 USD ($) shares	Apr. 23, 2018 USD ($)
Class of Stock [Line Items]
Stock split, conversion ratio		2
Shares withheld for tax withholding and exercise of options (in shares) | shares						7,795	41,962
Amount of shares withheld for tax withholding and exercise of options						$ 326,000	$ 1,500,000
Shares withheld for tax withholding and exercise of options, weighted average price (in usd per share) | $ / shares						$ 41.84	$ 35.68
Share Repurchase Program, amount approved to repurchase									$ 25,000,000.0
Stock repurchased, net of commissions			$ 2,726,000	$ 1,435,000		$ 13,170,000	$ 1,539,000	$ 20,200,000
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%
Retained Earnings
Class of Stock [Line Items]
Reclassification from AOCI to retained earnings for stranded income tax effects					$ 638,000		$ 638,000
Common Stock
Class of Stock [Line Items]
Stock repurchased, net of commissions (in shares) | shares			65,127	33,090		313,651	35,886	484,868
Stock repurchased, net of commissions			$ 2,726,000	$ 1,435,000		$ 13,170,000	$ 1,539,000
Subsequent Event
Class of Stock [Line Items]
Dividends declared per common share (in usd per share) | $ / shares	$ 0.21

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