Stockholders' Equity - Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Per Share
Common Stock (in USD per share)	$ 0.87	$ 0.87	$ 1.7400	$ 1.7400
Series I Preferred Stock (in USD per share)			$ 0	$ 1.6250
Amount
Common Stock			$ 698,437	$ 647,098
Series I Preferred Stock			0	23,352
Totals			$ 698,437	$ 670,450

Aggregate dividends paid during the period for each share of common stock outstanding.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Amount of cash outflow in the form of ordinary dividends to preferred shareholders of the parent entity.

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Cash outflow in the form of ordinary dividends to common shareholders, preferred shareholders and noncontrolling interests, generally out of earnings.

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Aggregate dividends paid during the period for each share of preferred stock outstanding.

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