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Common Stock and Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands					1 Months Ended
	May 06, 2019	Apr. 15, 2019	Apr. 16, 2018	Apr. 09, 2017	Apr. 30, 2009	Apr. 09, 2019
Common Stock and Dividends
Cash dividends paid to common shareholders (in dollars per share)		$ 0.50	$ 0.33
Repurchase of common stock, authorized amount					$ 40,000	$ 50,000
Period of repurchase of common stock				12 months	12 months
Cumulative number of shares repurchased under all stock repurchase programs	9,801,561
Cumulative cost of shares repurchased under all stock repurchase programs	$ 311,359

X

- Definition

The cumulative cost of shares that have been repurchased under all stock repurchase programs as of a certain date.

+ References

No definition available.

+ Details

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Period Type:	duration

X

- Definition

The cumulative number of shares that have been repurchased under all stock repurchase programs as of a certain date.

+ References

No definition available.

+ Details

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X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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X

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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X

- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

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- References

No definition available.

+ Details

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