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Stockholders' Equity (Narrative) (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Feb. 14, 2018
Class of Stock [Line Items]
Common stock repurchased	$ 85,000	$ 1,300,000	$ 55,000
2018 Stock Repurchase Program
Class of Stock [Line Items]
Stock repurchase program, authorized amount						$ 25,000,000
Shares Outstanding Class A | 2018 Stock Repurchase Program
Class of Stock [Line Items]
Common stock repurchased (in shares)	2,230		1,668	38,524	1,668.000000
Common stock repurchased	$ 100,000		$ 100,000	$ 1,400,000	$ 100,000

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