Stockholders' Equity (Details) - USD ($) shares in Thousands, $ in Thousands	9 Months Ended	28 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Jun. 30, 2017
Stockholders' Equity
Cost of shares of common stock repurchased	$ 1,056	$ 4,826
Common Stock
Stockholders' Equity
Authorized stock repurchase amount				$ 50,000
Shares of common stock repurchased	51	236	816
Cost of shares of common stock repurchased	$ 1,056	$ 4,826	$ 14,948

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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration