Reconciliation of Segment Operating Income (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014
Reconciliation Of Segment Operating Income Details
Total operating income									$ 7,347,006	$ 7,394,461
Interest expense, net									565,212	473,486
Other expense, net									167,397	118,250
Consolidated income before taxes									6,614,397	6,802,725
Net income	$ 440,000	$ 1,208,000	$ 2,710,000	$ 436,000	$ 689,000	$ 1,189,000	$ 2,543,000	$ 368,000	$ 4,793,525	$ 4,789,005