Earnings Per Share (Reconciliation Of Basic And Diluted Net Income Per Share) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Numerator [Abstract]
Net income attributable to CAI common stockholders used in the calculation of basic and diluted earnings per share	$ 13,446	$ 16,931	$ 27,717	$ 32,998
Denominator [Abstract]
Weighted average shares used in the calculation of basic earnings per share (in shares)	21,910	22,144	22,061	22,115
Effect of dilutive securities, Stock options and restricted stock (in shares)	445	567	445	575
Weighted average shares used in the calculation of diluted earnings per share (in shares)	22,355	22,711	22,506	22,690
Net income per share attributable to CAI common stockholders [Abstract]
Basic (in dollars per share)	$ 0.61	$ 0.76	$ 1.26	$ 1.49
Diluted (in dollars per share)	$ 0.60	$ 0.75	$ 1.23	$ 1.45