v2.4.0.8

Stockholders' Equity (Details) (USD $) | 0 Months Ended | 9 Months Ended |  |  | 0 Months Ended |  |  | 9 Months Ended | 0 Months Ended | 9 Months Ended |  |  | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 30, 2014 | Jan. 29, 2014 | Sep. 30, 2014 | Sep. 30, 2013 | Sep. 11, 2014 | Dec. 31, 2013 | Jun. 03, 2014 New ATM program [Member] Y | Sep. 30, 2014 New ATM program [Member] | Jun. 02, 2014 Atm Program [Member] | Sep. 30, 2014 Quarter 4 2013 [Member] | Sep. 30, 2014 Quarter 1 2014 [Member] | Sep. 30, 2014 Quarter 2 2014 [Member] | Sep. 30, 2014 Quarter 3 2014 [Member] | Aug. 15, 2014 Series B Cumulative Redeemable Preferred Stock [Member] | May 15, 2014 Series B Cumulative Redeemable Preferred Stock [Member] | Feb. 18, 2014 Series B Cumulative Redeemable Preferred Stock [Member] | Sep. 30, 2014 Series B Cumulative Redeemable Preferred Stock [Member] | Sep. 11, 2014 Series B Cumulative Redeemable Preferred Stock [Member] | Dec. 31, 2013 Series B Cumulative Redeemable Preferred Stock [Member] | Sep. 30, 2014 Series B Cumulative Redeemable Preferred Stock [Member] Quarter 1 2014 [Member] | Sep. 30, 2014 Series B Cumulative Redeemable Preferred Stock [Member] Quarter 2 2014 [Member] | Sep. 30, 2014 Series B Cumulative Redeemable Preferred Stock [Member] Quarter 3 2014 [Member] | Sep. 30, 2014 Series B Cumulative Redeemable Preferred Stock [Member] Quarter 4 2014 [Member] | Mar. 27, 2018 Depository shares of Series B Cumulative Redeemable Preferred [Member] | Sep. 30, 2014 Depository shares of Series B Cumulative Redeemable Preferred [Member] | Mar. 27, 2018 Subsequent Event [Member] Series B Cumulative Redeemable Preferred Stock [Member]
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares outstanding |  |  | 153,099,786 |  |  | 152,983,101 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At the market stock offering program, aggregate value of common stock |  |  |  |  |  |  | $ 600,000,000 |  | $ 600,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At Market Stock Offering Program Maximum Length Of Sale In Years |  |  |  |  |  |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At the market stock offering program remaining amount available for issuance |  |  |  |  |  |  |  |  | 305,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares of its Common Stock in connection with the redemption of an equal number of OP Units |  |  | 70,422 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares of Common Stock upon the exercise of options to purchase Common Stock by certain employees (in shares) |  |  | 17,124 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend payable date |  |  |  |  |  |  |  |  |  | Jan. 29, 2014 | Apr. 30, 2014 | Jul. 31, 2014 | Oct. 31, 2014 |  |  |  |  |  |  | Feb. 18, 2014 | May 15, 2014 | Aug. 15, 2014 | Nov. 17, 2014 |  |  |
Dividend paid on common stock (in dollars per share) | $ 0.65 | $ 2.90 |  |  |  |  |  |  |  |  |  |  |  | $ 32.8125 | $ 32.8125 | $ 32.8125 |  |  |  |  |  |  |  |  |  |
Dividend shareholder of record date |  |  |  |  |  |  |  |  |  | Dec. 31, 2013 | Mar. 31, 2014 | Jun. 30, 2014 | Sep. 30, 2014 |  |  |  |  |  |  |  |  |  | Nov. 05, 2014 |  |  |
Dividends payable, date declared |  |  |  |  |  |  |  |  |  |  |  |  | Sep. 11, 2014 |  |  |  |  |  |  |  |  |  | Sep. 11, 2014 |  |  |
Dividends Payable, Amount Per Share |  |  |  |  | $ 0.65 |  |  |  |  |  |  |  |  |  |  |  |  | $ 32.8125 |  |  |  |  |  |  |  |
Series B, Shares Outstanding |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 80,000 |  | 80,000 |  |  |  |  |  | 8,000,000 |
Series B, Dividend Rate, Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.25% |  |  |  |  |  |  |  |  |
Series B, Liquidation Preference Per Share |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,500.00 |  | $ 2,500 |  |  |  |  | $ 25.00 | $ 25.00 | $ 2,500.00
Proceeds from Issuance of Series B |  |  | 0 | 193,623,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ratio of depository shares to shares of Series B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.01 |  |  |  |  |  |  |  |  |
Common Stock, Value, Issued |  |  | $ 1,531,000 |  |  | $ 1,530,000 |  | $ 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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