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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Period Type:	duration

Stockholders' Equity (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended			60 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Jun. 30, 2017
Stockholders' Equity
Cost of shares of common stock repurchased	$ 1,056	$ 467
Common Stock
Stockholders' Equity
Authorized stock repurchase amount					$ 50,000
Shares of common stock repurchased	51	260	505	816
Cost of shares of common stock repurchased	$ 1,056	$ 5,293	$ 8,599	$ 14,948