Earnings Per Share (Reconciliation Of Basic And Diluted Net Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Net income attributable to CAI common stockholders	$ 19,149	$ 12,638	$ 36,266	$ 17,910
Weighted-average shares used in per share computation - basic	19,613	19,131	20,013	19,071
Effect of dilutive securities: Stock options and restricted stock	230	288	245	261
Weighted-average shares used in per share computation - diluted	19,843	19,419	20,259	19,332
Basic	$ 0.98	$ 0.66	$ 1.81	$ 0.94
Diluted	$ 0.97	$ 0.65	$ 1.79	$ 0.93

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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