Shareholders' Equity - Schedule of Amount Received in Connection With DRIP (Details) - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Amounts Received	[1]	$ 22,400,945	$ 24,599,818	$ 32,792,239
Dividend Reinvestment Stock Purchase Plan [Member]
Class of Stock [Line Items]
Amounts Received		22,400,945	24,599,818	32,792,239
Less: Dividends Reinvested		(2,388,552)	(2,006,287)	(1,858,491)
Amounts Received, net		$ 20,012,393	$ 22,593,531	$ 30,933,748
Number of Shares Issued		1,966,133	2,657,255	3,554,191

[1] Dividend Reinvestment and Stock Purchase Plan.