Earnings Per Share - Computations Of Basic And Diluted EPS (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Basic:
Net income attributable to common shareholders	$ 31,695	$ 27,121	$ 49,867	$ 42,345
Less: Undistributed earnings allocated to participating securities	(261)	(260)	(435)	(407)
Accretion of redeemable noncontrolling interests	(25)	0	(43)	0
Net income available to common shareholders, basic	$ 31,409	$ 26,861	$ 49,389	$ 41,938
Weighted average number of shares outstanding, basic (in shares)	147,575	146,700	147,506	146,679
Effect of dilutive securities:
Net income available to common shareholders, basic	$ 31,409	$ 26,861	$ 49,389	$ 41,938
Share-based awards other than participating securities	$ 0	$ 0	$ 0	$ 0
Share-based awards other than participating securities (in shares)	779	264	580	82
Undistributed earnings reallocated to participating securities	$ 1	$ 0	$ 2	$ 0
Net income available to common shareholders, diluted	$ 31,410	$ 26,861	$ 49,391	$ 41,938
Weighted average number of shares outstanding, diluted (in shares)	148,354	146,964	148,086	146,761