v3.3.1.900

Share-Based Compensation (Details Textuals) - USD ($) $ / shares in Units, $ in Millions |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 27, 2015 | Apr. 04, 2013 | Feb. 22, 2012 | Feb. 28, 2012 | Dec. 31, 2012 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  | 212,468 |  |  |  |  |
Grant date fair value per share |  |  |  |  |  |  |  |  |  | $ 65.03 |  |  |
Trading price of the company's stock |  | $ 75.34 |  |  |  |  |  |  |  |  |  |  |
Allocated Share-based Compensation Expense |  |  |  |  |  | $ 9.6 |  | $ 18.9 |  | $ 14.5 |  |  |
Share-based compensation cost capitalized as part of real estate assets |  |  |  |  |  | $ 0.9 |  | $ 3.3 |  | $ 2.3 |  |  |
Total unrecognized compensation cost weighted-average period |  |  |  |  |  |  |  | 1 year 11 months |  |  |  |  |
Total unrecognized compensation cost related to nonvested incentive awards granted |  |  |  |  |  |  |  |  |  |  |  |  | $ 31.2
Market Measure-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  | 127,657 |  | 119,098 |  |  |
Grants in period, grant date fair value |  |  |  |  |  |  |  | $ 10.1 |  |  |  |  |
Grant date fair value per share |  | $ 78.55 |  |  |  | $ 44.55 | [1] | $ 79.25 | [1],[2] |  | $ 64.86 | [1] |
Expected share price volatility |  |  |  |  |  |  |  | 20.00% |  | 24.00% |  |  |
Risk-free interest rate |  |  |  |  |  |  |  | 0.92% |  | 0.61% |  |  |
Expected life |  | 2 years 11 months |  |  |  |  |  |  |  | 2 years 7 months |  |  |
Time-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  | 84,811 |  | 117,506 |  |  |
Grant date fair value per share |  |  |  |  |  | $ 49.45 |  | $ 74.49 |  |  | $ 59.89 |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  |  |  | 213 | 0 |  |
Grant date fair value per share |  |  |  |  |  |  |  | $ 0.00 |  | $ 51.35 | $ 0.00 |  |
Stock Options [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Expected share price volatility |  |  |  |  | 33.00% |  |  |  |  |  |  |  |
Risk-free interest rate |  |  |  |  | 1.35% |  |  |  |  |  |  |  |
Expected life |  |  |  |  | 6 years 6 months |  |  |  |  |  |  |  |
Kilroy Realty 2006 Incentive Award Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares Available for Grant |  |  |  |  |  |  |  | 1,686,608 |  |  |  |  |
Kilroy Realty 2006 Incentive Award Plan [Member] | Stock Options [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Options, Withheld in Period |  |  |  |  |  |  |  | 62,072 |  |  |  |  |
Options, Withheld in Period, Intrinsic Value |  |  |  |  |  |  |  | $ 3.9 |  |  |  |  |
Minimum [Member] | Executive Officer Share-Based Compensation Programs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Service Vesting Period |  |  |  |  |  |  |  | 1 year |  |  |  |  |
Maximum [Member] | Executive Officer Share-Based Compensation Programs [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Service Vesting Period |  |  |  |  |  |  |  | 5 years |  |  |  |  |
Chief Executive Officer [Member] | Executive Officer Share-Based Compensation Programs [Member] | Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  | 236,604 |  |  |  |  |  |  |  |  |  |
Chief Executive Officer [Member] | Executive Officer Share-Based Compensation Programs [Member] | Market Measure-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Grants in period, grant date fair value |  |  | $ 7.7 |  |  |  |  |  |  |  |  |  |
Chief Executive Officer [Member] | Executive Officer Share-Based Compensation Programs [Member] | Time-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise Price |  |  | $ 60.16 |  |  |  |  |  |  |  |  |  |
Management [Member] | Stock Options [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Award vesting period |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Options granted in period |  |  |  | 1,550,000 |  |  |  |  |  |  |  |  |
Trading price of the company's stock |  |  |  | $ 42.61 |  |  |  |  |  |  |  |  |
Expiration period |  |  |  | 10 years |  |  |  |  |  |  |  |  |
Nonvested Restricted Stock Units R S U [Member] | Market Measure-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  | 9,542 |  | 191,483 |  |  | 183,365 |  |
Nonvested Restricted Stock Units R S U [Member] | Time-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  | 173,758 |  | 98,802 |  |  | 155,016 |  |
Number of shares that were tendered to satisfy minimum statutory tax withholding requirements | [3] |  |  |  |  |  |  | 5,354 |  |  |  |  |
Nonvested Restricted Stock Units R S U [Member] | Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  | 0 |  |  |  |  |
Vested Restricted Stock Units R S U [Member] | Market Measure-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  | 0 |  |  |  |  |
Vested Restricted Stock Units R S U [Member] | Time-Based Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  |  |  |  | 0 |  |  |  |  |
Number of shares that were tendered to satisfy minimum statutory tax withholding requirements |  |  |  |  |  |  |  | 20,042 |  |  |  |  |
Vested Restricted Stock Units R S U [Member] | Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares that were tendered to satisfy minimum statutory tax withholding requirements |  |  |  |  |  |  |  | 10,699 |  |  |  |  |
Shareholder Meeting Date May 21, 2015 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Shares Requested |  |  |  |  |  |  |  | 8,320,000 |  |  |  |  |
[1] | (1)Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant. As discussed above, the 2014 Performance-Based RSU Grant was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014.
[2] | Represents the grant-date fair value for all awards, excluding the 2014 Performance-Based RSU Grant. As discussed above, the 2014 Performance-Based RSU Grant was re-measured upon stockholder approval of the amended 2006 Plan on May 22, 2014.
[3] | (4)For shares vested but not yet settled, we accept the return of RSUs at the current quoted closing share price of the Company’s common stock to satisfy minimum statutory tax-withholding requirements related to either the settlement or vesting of RSUs in accordance with the terms of the 2006 Plan.

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- Definition The total fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans. + References No definition available. + Details
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- Definition The maximum number of shares (or other type of equity) to be approved (usually by shareholders and board of directors) by shareholders. + References No definition available. + Details
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
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- Definition Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition Price of a single share of a number of saleable stocks of a company. + References No definition available. + Details
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- Definition Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section D -Subsection 2 + Details
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- Definition For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer. + References No definition available. + Details
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