No definition available.

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The cash outflow to reacquire common stock during the period.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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

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Earnings Per Share - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 26, 2018
Earnings Per Share [Line Items]
Share repurchase program				$ 20,000
Stock repurchased during period (in shares)		92,987
Purchase shares under the repurchase program	$ 20,000
Common stock at a weighted-average price (in dollars per share)		$ 32.90
Payments for repurchase of common stock	$ 1,043	$ 3,058	$ 101,483
Shares Repurchased Under Stock Compensation Program [Member]
Earnings Per Share [Line Items]
Stock repurchased during period (in shares)	32,857	57,649
Stock repurchased during period, values	$ 1,000	$ 2,200
Share Repurchase Program [Member]
Earnings Per Share [Line Items]
Stock repurchased during period (in shares)		35,338
Payments for repurchase of common stock		$ 800