Equity And Earnings Per Share (Diluted Table) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Diluted earnings per share:
Net income available for common stockholders	$ 15,161	$ 10,378	$ 34,250	$ 16,935
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	56,079,813	48,929,348	55,375,929	48,218,572
Potentially dilutive common shares:
Issuable pursuant to 2007 ROI Unit Stock Plan	1,220,417	83,219	1,298,737	135,526
Weighted Average Number of Shares Outstanding, Diluted	57,300,230	49,012,567	56,674,666	48,354,098
Earnings Per Share, Diluted	$ 0.26	$ 0.21	$ 0.60	$ 0.35
Common Class A
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	56,079,713	48,929,248	55,375,829	48,218,472
Common Class B
Weighted Average Shares Outstanding [Abstract]
Weighted Average Number of Shares Outstanding, Basic	100	100	100	100

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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 or Loss Available to Common Stockholders plus 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 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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