Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2018
Commitments and Contingencies [Line Items]
Commitments and Contingencies	Commitments and Contingencies In addition to the commitments and contingencies disclosed elsewhere and previously disclosed, the Company has the following commitments and contingencies. The Company is obligated under certain tenant leases, including its proportionate share for leases for non-consolidated entities, to fund the expansion of the underlying leased properties. The Company, under certain circumstances, may guarantee to tenants the completion of base building improvements and the payment of tenant improvement allowances and lease commissions on behalf of its subsidiaries. The Company and LCIF are parties to a funding agreement under which the Company may be required to fund distributions made on account of LCIF's OP units. Pursuant to the funding agreement, the parties agreed that, if LCIF does not have sufficient cash available to make a quarterly distribution to its limited partners in an amount in accordance with the partnership agreement, Lexington will fund the shortfall. Payments under the agreement will be made in the form of loans to LCIF and will bear interest at prevailing rates as determined by the Company in its discretion, but no less than the applicable federal rate. LCIF's right to receive these loans will expire if no OP units remain outstanding and all such loans are repaid. No amounts have been advanced under this agreement. From time to time, the Company is directly and indirectly involved in legal proceedings arising in the ordinary course of business. Management believes, based on currently available information, and after consultation with legal counsel, that although the outcomes of those normal course proceedings are uncertain, the results of such proceedings, in the aggregate, will not have a material adverse effect on the Company's business, financial condition and results of operations.
LCIF [Member]
Commitments and Contingencies [Line Items]
Commitments and Contingencies	Commitments and Contingencies In addition to the commitments and contingencies disclosed elsewhere, the Partnership has the following commitments and contingencies. The Partnership is obligated under certain tenant leases, including its proportionate share for leases for non-consolidated entities, to fund the expansion of the underlying leased properties. The Partnership, under certain circumstances, may guarantee to tenants the completion of base building improvements and the payment of tenant improvement allowances and lease commissions on behalf of its subsidiaries. The Partnership and Lexington are parties to a funding agreement under which Lexington may be required to fund distributions made on account of OP units. Pursuant to the funding agreement, if the Partnership does not have sufficient cash available to make a quarterly distribution to its limited partners in an amount in accordance with the partnership agreement, Lexington is required to fund the shortfall. Payments under the agreement will be made in the form of loans to the Partnership and will bear interest at prevailing rates as determined by Lexington in its discretion, but no less than the applicable federal rate. The Partnership's right to receive these loans will expire if no OP units remain outstanding and all such loans are repaid. No amounts had been advanced under this funding agreement. The Partnership has guaranteed $250,000 aggregate principal amount of 4.40% Senior Notes due 2024 (“2024 Senior Notes”) issued by Lexington at an issuance price of 99.883% of the principal amount and $250,000 aggregate principal amount of 4.25% Senior Notes due 2023 (“2023 Senior Notes”) issued by Lexington at an issuance price of 99.026% of the principal amount, collectively referred to as the Senior Notes. The Senior Notes are unsecured and pay interest semi-annually in arrears. Lexington may redeem the Senior Notes at its option at any time prior to maturity in whole or in part by paying the principal amount of the notes being redeemed plus a premium. From time to time, the Partnership is directly or indirectly involved in legal proceedings arising in the ordinary course of the Partnership's business. The Partnership believes, based on currently available information, and after consultation with legal counsel, that although the outcomes of those normal course proceedings are uncertain, the results of such proceedings, in the aggregate, will not have a material adverse effect on the Partnership's business, financial condition and results of operations.