[Line Items] for Schedule of Shareholders' Equity [Table]

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- Definition

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

+ References

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-Topic 505
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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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- Definition

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

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Stockholders' Equity (Details) - USD ($)				1 Months Ended	3 Months Ended		9 Months Ended		112 Months Ended	155 Months Ended	171 Months Ended
Stockholders' Equity (Details) - USD ($)	May 20, 2019	Nov. 08, 2018	May 18, 2018	Oct. 29, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2019	Feb. 28, 2019	May 15, 2018	May 19, 2015
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)							365,886	513,875			13,462,690
Aggregate price of shares repurchased since inception							$ 16,460,000	$ 18,361,000			$ 204,982,000
Average price of shares repurchased since inception (per share)							$ 44.99	$ 35.73			$ 15.23
Cash dividends declared per common share (in dollars per share)					$ 0	$ 0	$ 0.16	$ 0.16
Dividend Declared
Schedule of Shareholders' Equity [Line Items]
Cash dividends declared per common share (in dollars per share)	$ 0.16	$ 0.16	$ 0.16
Open market
Schedule of Shareholders' Equity [Line Items]
Stock repurchase program amount authorized (in shares)														5,700,000
Stock repurchase program, authorized amount												$ 20,000,000.0	$ 15,000,000.0
Stock repurchased during period (in shares)							5,799	116,289	4,101,566
Aggregate price of shares repurchased since inception							$ 200,000	$ 3,840,000	$ 69,806,000
Average price of shares repurchased since inception (per share)							$ 34.46	$ 33.02	$ 17.02
401(k)
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)							335,139	373,129			7,382,915
Aggregate price of shares repurchased since inception							$ 15,237,000	$ 13,661,000			$ 115,778,000
Average price of shares repurchased since inception (per share)							$ 45.46	$ 36.61			$ 15.68
401(k) \| Subsequent Event
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)				27,532
Aggregate price of shares repurchased since inception				$ 1,300,000
Directors and employees
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)							24,948	24,457		1,978,209
Aggregate price of shares repurchased since inception							$ 1,023,000	$ 860,000		$ 19,398,000
Average price of shares repurchased since inception (per share)							$ 41.00	$ 35.15		$ 9.81