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

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-Publisher FASB
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-Topic 230
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-Section 45
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- Definition

The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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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.

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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.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Subsequent Events - Narrative (Details) - USD ($) $ in Thousands				12 Months Ended
	Feb. 11, 2019	Jan. 29, 2019	Jan. 15, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 01, 2019
Subsequent Event [Line Items]
Payments of dividends, common stock				$ 179,411	$ 340,697	$ 137,444
Repayments of secured debt				$ 3,584	130,371	74,140
Kilroy Realty 2006 Incentive Award Plan [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares available for grant				600,000
Subsequent event [Member]
Subsequent Event [Line Items]
Payments of dividends, common stock			$ 47,500
Subsequent event [Member] \| Kilroy Realty 2006 Incentive Award Plan [Member] \| Time-Based Restricted Stock Units (RSUs) [Member] \| Chief Executive Officer [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares available for grant		144,982
Subsequent event [Member] \| Kilroy Realty 2006 Incentive Award Plan [Member] \| Market measure-based Restricted Stock Units (RSUs) [Member] \| Chief Executive Officer [Member]
Subsequent Event [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares available for grant							143,396
Share-based compensation arrangement by share-based payment award, award requisite service period		3 years
Kilroy Realty L.P. [Member]
Subsequent Event [Line Items]
Payments of dividends, common stock				$ 179,411	340,697	137,444
Repayments of secured debt				$ 3,584	$ 130,371	$ 74,140
Secured debt [Member] \| 6.05% Mortgage Payable Due June 1, 2019 [Member] \| Kilroy Realty L.P. [Member] \| Subsequent event [Member]
Subsequent Event [Line Items]
Repayments of secured debt	$ 74,300