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Long-term Debt, Percentage Bearing Fixed Interest, Remaining Commitments

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Long-term Debt, Percentage Bearing Variable Interest, Remaining Commitments

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Long-term debt, remaining commitments

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Consolidated and unconsolidated real estate joint ventures Unconsolidated real estate joint ventures (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 192,972		$ 110,618
Weighted-Average Interest Rate at End of Period	4.01%
Long-term Debt	$ 5,614,105
Equity Method Investee
Schedule of Equity Method Investments
Long-term Debt	319,925
Long-term Debt, Remaining Commitments	510,741
Equity Method Investee \| Menlo Gateway
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	121,785
Equity Method Investee \| 1401/1413 Research Boulevard
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 7,533
Equity interest percentage (in percent)	65.00%
Equity Method Investee \| 360 Longwood Avenue
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 25,538
Equity interest percentage (in percent)	27.50%
Equity Method Investee \| 704 Quince Orchard Road
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 4,384
Equity interest percentage (in percent)	56.80%	56.80%
Equity Method Investee \| 1655 and 1725 Third Street
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 33,732
Equity interest percentage (in percent)	10.00%	10.00%
Initial ownership interest \| Equity Method Investee \| Menlo Gateway
Schedule of Equity Method Investments
Equity interest percentage (in percent)	29.40%
Secured debt maturing on 3/1/19 \| Equity Method Investee \| Menlo Gateway
Schedule of Equity Method Investments
Maturity Date	Mar. 01, 2019
Weighted-Average Interest Rate at End of Period	4.49%
Long-term Debt	$ 134,564
Long-term Debt, Percentage Bearing Variable Interest, Remaining Commitments	$ 13,290
Secured debt maturing on 5/17/20 \| Equity Method Investee \| 1401/1413 Research Boulevard
Schedule of Equity Method Investments
Maturity Date	May 17, 2020
Weighted-Average Interest Rate at End of Period	5.39%
Long-term Debt	$ 14,682
Long-term Debt, Percentage Bearing Variable Interest, Remaining Commitments	$ 9,892
Secured debt maturing on 6/29/21 \| Equity Method Investee \| 1655 and 1725 Third Street
Schedule of Equity Method Investments
Maturity Date	Jun. 29, 2021
Weighted-Average Interest Rate at End of Period	5.68%
Long-term Debt	$ 75,520
Long-term Debt, Percentage Bearing Variable Interest, Remaining Commitments	$ 299,480
Secured debt maturing on 9/1/22 \| Equity Method Investee \| 360 Longwood Avenue
Schedule of Equity Method Investments
Maturity Date	Sep. 01, 2022
Stated interest rate (as a percent)	3.32%
Weighted-Average Interest Rate at End of Period	3.54%
Long-term Debt	$ 94,143
Long-term Debt, Percentage Bearing Fixed Interest, Remaining Commitments	17,000
Earn-out provisions for incremental borrowing	$ 48,000
Secured debt maturing on 3/16/23 \| Equity Method Investee \| 704 Quince Orchard Road
Schedule of Equity Method Investments
Maturity Date	Mar. 16, 2023
Weighted-Average Interest Rate at End of Period	4.29%
Long-term Debt	$ 1,016
Long-term Debt, Percentage Bearing Variable Interest, Remaining Commitments	$ 13,809
Secured debt maturing on 5/1/35 \| Equity Method Investee \| Menlo Gateway
Schedule of Equity Method Investments
Maturity Date	May 01, 2035
Stated interest rate (as a percent)	4.53%
Weighted-Average Interest Rate at End of Period	4.56%
Long-term Debt	$ 0
Long-term Debt, Percentage Bearing Fixed Interest, Remaining Commitments	$ 157,270
London Interbank Offered Rate (LIBOR) \| Secured debt maturing on 3/1/19 \| Equity Method Investee \| Menlo Gateway
Schedule of Equity Method Investments
Applicable margin (as a percent)	2.50%
London Interbank Offered Rate (LIBOR) \| Secured debt maturing on 5/17/20 \| Equity Method Investee \| 1401/1413 Research Boulevard
Schedule of Equity Method Investments
Applicable margin (as a percent)	2.50%
London Interbank Offered Rate (LIBOR) \| Secured debt maturing on 6/29/21 \| Equity Method Investee \| 1655 and 1725 Third Street
Schedule of Equity Method Investments
Applicable margin (as a percent)	3.70%
London Interbank Offered Rate (LIBOR) \| Secured debt maturing on 3/16/23 \| Equity Method Investee \| 704 Quince Orchard Road
Schedule of Equity Method Investments
Applicable margin (as a percent)	1.95%