v3.3.1.900

Preferred and Common Units of the Operating Partnership (Details Textuals) - USD ($) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 18, 2013 | Oct. 23, 2014 | Sep. 30, 2013 | Aug. 31, 2012 | Mar. 31, 2012 | Dec. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Jul. 01, 2015 | Jun. 30, 2015 | Jan. 27, 2015
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  |  |  | 3,773,766 |  |  |
Shares Issued, Price Per Share |  |  |  |  |  |  |  |  |  | $ 66.19 |  |  |
At Market Stock Aggregate Gross Sales Price of Common Stock |  |  |  |  |  |  |  |  |  | $ 249,800 |  |  |
Proceeds from Issuance of Common stock, net |  |  |  |  |  | $ 249,600 |  |  |  |  |  |  |
purchase price, value of shares issued to acquire land |  |  |  |  |  |  | $ 0 | $ 21,631 | $ 0 |  |  |  |
Net proceeds from issuance of common stock |  |  |  |  |  |  | $ 387,398 | $ 102,229 | $ 349,951 |  |  |  |
Share price per unit of common units issued (dollars per unit) |  |  |  |  |  |  |  |  |  |  |  |  | $ (75.34)
Series H Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred units issued |  |  |  |  |  |  |  |  | 4,000,000 |  |  |  |
Preferred stock, dividend rate |  |  |  | 6.375% |  |  | 6.375% |  | 6.375% |  |  |  |
Preferred Stock, Shares Outstanding |  |  |  |  |  | 4,000,000 | 4,000,000 | 4,000,000 |  |  |  |  |
Series H Cumulative Redeemable Preferred Stock | Series H Cumulative Redeemable Preferred Unit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred units issued |  |  |  |  |  |  |  |  |  |  | 4,000,000 |  |
Series G Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred units issued |  |  |  |  |  |  |  |  | 4,000,000 |  |  |  |
Preferred stock, dividend rate |  |  |  |  | 6.875% |  | 6.875% |  | 6.875% |  |  |  |
Preferred Stock, Shares Outstanding |  |  |  |  |  | 4,000,000 | 4,000,000 | 4,000,000 |  |  |  |  |
Series G Cumulative Redeemable Preferred Stock | Series G Cumulative Redeemable Preferred Unit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred units issued |  |  |  |  |  | 4,000,000 | 4,000,000 |  |  |  |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  |  |  |  |  |  |  |  | 86,259,684 |  | 92,258,690 |  |
Kilroy Realty, L.P. [Member] | Market Measure-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of RSUs outstanding |  |  |  |  |  |  |  |  | 247,089 |  | 425,452 | [1] |
Kilroy Realty, L.P. [Member] | Series H Cumulative Redeemable Preferred Unit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred units issued |  |  |  |  |  |  |  |  | 4,000,000 |  | 4,000,000 |  |
Preferred units outstanding |  |  |  |  |  | 4,000,000 | 4,000,000 |  | 4,000,000 |  |  |  |
Preferred stock, dividend rate |  |  |  |  |  |  | 6.375% |  | 6.375% |  |  |  |
Kilroy Realty, L.P. [Member] | Series G Cumulative Redeemable Preferred Unit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred units issued |  |  |  |  |  |  |  |  | 4,000,000 |  | 4,000,000 |  |
Preferred units outstanding |  |  |  |  |  | 4,000,000 | 4,000,000 |  | 4,000,000 |  |  |  |
Preferred stock, dividend rate |  |  |  |  |  |  | 6.875% |  | 6.875% |  |  |  |
Kilroy Realty, L.P. [Member] | Partners Capital Common Unit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common units, units |  |  | 6,175,000 |  |  |  |  |  | 7,210,838 |  |  |  |
Issuance of Equity - equity offering [Domain] | Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Share of common stock sold during the period |  |  | 6,175,000 |  |  |  |  |  |  |  |  |  |
Issuance of Equity - equity offering [Domain] | Common Stock | Issuance of Equity - equity offering [Domain] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock | $ 295,900 |  |  |  |  |  |  |  |  |  |  |  |
SFFGA [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Shares, Issued |  | 351,476 |  |  |  |  |  |  |  |  |  |  |
purchase price, value of shares issued to acquire land |  | $ 21,600 |  |  |  |  |  |  |  |  |  |  |
[1] | The amount includes nonvested RSUs. Does not include the 425,452 and 247,089 market measure-based RSUs because not all the necessary performance conditions have been met as of December 31, 2015 and 2014, respectively.

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