Equity - Earnings Per Share (EPS) (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Weighted-average number of shares outstanding:
Common stock (in shares)	20,855,112	20,724,689	20,841,627	20,713,396
Common stock equivalents-stock options, grants (in shares)	22,837	115,693	44,003	103,664
Diluted shares outstanding (in shares)	20,877,949	20,840,382	20,885,630	20,817,060