Earnings Per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Weighted-average shares:
Common shares outstanding	77,989,933	80,566,400	78,230,011	80,565,754
Restricted common shares	680,249	645,427	646,299	604,179
Total Weighted Average Shares	78,670,182	81,211,827	78,876,310	81,169,933
Percentage of weighted-average shares:
Common shares outstanding	99.14%	99.21%	99.18%	99.26%
Restricted common shares	0.86%	0.79%	0.82%	0.74%
Total	100.00%	100.00%	100.00%	100.00%