Earnings Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Weighted-average shares:
Common shares outstanding	74,477,865	77,447,263	78,219,458
Restricted common shares	495,192	476,726	556,592
Total weighted average shares	74,973,057	77,923,989	78,776,050
Percentage of weighted-average shares:
Common shares outstanding	99.34%	99.39%	99.29%
Restricted common shares	0.66%	0.61%	0.71%
Total	100.00%	100.00%	100.00%