Earnings Per Share - Computations Of Basic And Diluted EPS (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Basic:
Net income attributable to common shareholders	$ 16,854	$ 17,784	$ 18,172	$ 15,224
Less: Undistributed earnings allocated to participating securities	(141)	(171)	(159)	(147)
Accretion of redeemable noncontrolling interests	(18)	0	(18)	0
Net income available to common shareholders, basic	$ 16,695	$ 17,613	$ 17,995	$ 15,077
Weighted average number of shares outstanding, basic (in shares)	147,521	146,683	147,471	146,668
Effect of dilutive securities:
Net income available to common shareholders, basic	$ 16,695	$ 17,613	$ 17,995	$ 15,077
Share-based awards other than participating securities	$ 0	$ 0	$ 0	$ 0
Share-based awards other than participating securities (in shares)	580	41	460	0
Net income available to common shareholders, diluted	$ 16,695	$ 17,613	$ 17,995	$ 15,077
Weighted average number of shares outstanding, diluted (in shares)	148,101	146,724	147,931	146,668

Accretion of redeemable noncontrolling interests to redemption value through retained earnings (equity classification).

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Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise of stock options or restrictive stock units (RSUs).

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent, and includes adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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The earnings that is allocated to common stock and participating securities to the extent that each security may share in earnings as if all of the earnings for the period had been distributed.

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