Stockholders' Equity - Common Stock Dividends and Buyback Program (Details) - USD ($)	3 Months Ended	53 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	May 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock outstanding (in shares)	33,003,134		33,003,134
Cash dividends to common stockholders	$ 3,306,408	$ 3,315,785
Shares forfeited (in shares)	8,939
Common Stock \| 2015 Share Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized amount to be repurchased				$ 5,000,000
Value of shares repurchased	$ 1,362,424	$ 89,992	$ 2,900,000
Treasury stock acquired (in shares)	222,437		488,629
Number of treasury shares acquired (in shares)	231,376	9,087
Average cost per share (in dollars per share)	$ 5.89	$ 9.90	$ 5.98

Treasury Stock, Shares, Acquired, Net of Shares Forfeited

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Amount of stock repurchase plan authorized.

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

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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