Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Feb. 06, 2018	Mar. 09, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 06, 2017
Subsequent Event [Line Items]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased						1,700,000
Shares repurchased			961,566	833,784	325,613
Stock Repurchased and Retired During Period, Value			$ 14,642	$ 14,028	$ 5,639
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividend Per Share	$ 0.41
Declared date	Feb. 06, 2018
Payment Date	Mar. 15, 2018
Record Date	Mar. 01, 2018
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	1,550,000
Shares repurchased		371,705
Stock Repurchased and Retired During Period, Value		$ 5,500