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, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net income attributable to CAI common stockholders used in the calculation of basic and diluted earnings per share	$ 12,638	$ 3,711	$ 17,910	$ 10,828
Weighted-average shares used in the calculation of basic earnings per share	19,131	19,372	19,071	19,577
Effect of dilutive securities: Stock options and restricted stock	288	77	261	69
Weighted-average shares used in the calculation of diluted earnings per share	19,419	19,449	19,332	19,646
Basic	$ 0.66	$ 0.19	$ 0.94	$ 0.55
Diluted	$ 0.65	$ 0.19	$ 0.93	$ 0.55

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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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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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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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