Balance Sheet Parenthetical (Parentheticals) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Treasury Stock, Shares	1,249,909us-gaap_TreasuryStockShares	1,249,909us-gaap_TreasuryStockShares
Common shares outstanding	149,807,179us-gaap_CommonStockSharesOutstanding	147,846,801us-gaap_CommonStockSharesOutstanding
Common Stock, Shares, Issued	149,807,179us-gaap_CommonStockSharesIssued	147,846,801us-gaap_CommonStockSharesIssued
Common Stock, Shares Authorized	283,987,000us-gaap_CommonStockSharesAuthorized	183,987,000us-gaap_CommonStockSharesAuthorized
Common Stock, Par or Stated Value Per Share	$ 0.001	$ 0.001
Redeemable Preferred Stock [Member]
Temporary Equity, Preferred Units, Outstanding	301,483	301,483
Liberty Property Limited Partnership [Member]
Limited Partners' units outstanding	3,553,566	3,556,566
Treasury Stock, Shares	1,249,909	1,249,909
Common shares outstanding	148,557,270	146,596,892
Liberty Property Limited Partnership [Member] \| Redeemable Preferred Stock [Member]
Temporary Equity, Preferred Units, Outstanding	301,483	301,483

Face amount or stated value per share of common stock.

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The number of limited partner units outstanding.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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