Stock Repurchase Program (Details Textual) - USD ($)			6 Months Ended	12 Months Ended
	Jan. 26, 2016	Mar. 24, 2015	Jun. 30, 2016	Dec. 31, 2015
Equity Class Of Treasury Stock [Line Items]
Percentage of shares authorized to be repurchased to common stock outstanding	2.30%	4.40%
Common stock, shares outstanding	4,404,783	4,527,849	4,420,255	4,404,783
Stock repurchase program, authorized amount		$ 3,100,000	$ 1,500,000
Stock repurchase program expiration date			Dec. 31, 2016
Stock repurchase program, shares repurchased				123,066
Maximum
Equity Class Of Treasury Stock [Line Items]
Shares authorized to be repurchased	100,000	200,000