Unconsolidated real estate joint ventures (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Schedule of Equity Method Investments
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 6,700
Investments in unconsolidated real estate joint ventures	$ 37,780	$ 38,435
Unconsolidated Real Estate Joint Venture Debt
Weighted Average Interest Rate at End of Period	3.72%
Long-term Debt	$ 11,315,642
1655 and 1715 Third Street
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 11,718	12,996
Unconsolidated Real Estate Joint Venture Debt
Equity interest percentage (in percent)	10.00%
1450 Research Boulevard
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 6,041	5,625
Unconsolidated Real Estate Joint Venture Debt
Equity interest percentage (in percent)	73.20%
101 West Dickman Street
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 9,290	8,678
Unconsolidated Real Estate Joint Venture Debt
Equity interest percentage (in percent)	57.90%
Other unconsolidated real estate joint ventures
Schedule of Equity Method Investments
Investments in unconsolidated real estate joint ventures	$ 10,731	$ 11,136
1401/1413 Research Boulevard
Unconsolidated Real Estate Joint Venture Debt
Equity interest percentage (in percent)	65.00%
Secured debt maturing on 12/23/24 \| 1401/1413 Research Boulevard
Unconsolidated Real Estate Joint Venture Debt
Maturity date	Dec. 23, 2024
Stated interest rate (as a percent)	2.70%
Weighted Average Interest Rate at End of Period	3.31%
Debt instrument, borrowing capacity	$ 28,500
Long-term Debt	$ 28,331
Secured debt maturing on 3/10/25 \| 1655 and 1715 Third Street
Unconsolidated Real Estate Joint Venture Debt
Maturity date	Mar. 10, 2025
Stated interest rate (as a percent)	4.50%
Weighted Average Interest Rate at End of Period	4.57%
Debt instrument, borrowing capacity	$ 600,000
Long-term Debt	$ 599,505
Secured debt maturing on 11/10/26 \| 101 West Dickman Street
Unconsolidated Real Estate Joint Venture Debt
Maturity date	Nov. 10, 2026
Weighted Average Interest Rate at End of Period	7.38%
Debt instrument, borrowing capacity	$ 26,750
Long-term Debt	$ 14,762
Secured debt maturing on 11/10/26 \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| 101 West Dickman Street
Unconsolidated Real Estate Joint Venture Debt
Stated interest rate (as a percent)	1.95%
Secured debt maturing on 12/10/26 \| 1450 Research Boulevard
Unconsolidated Real Estate Joint Venture Debt
Maturity date	Dec. 10, 2026
Weighted Average Interest Rate at End of Period	7.44%
Debt instrument, borrowing capacity	$ 13,000
Long-term Debt	$ 8,280
Secured debt maturing on 12/10/26 \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| 1450 Research Boulevard
Unconsolidated Real Estate Joint Venture Debt
Stated interest rate (as a percent)	1.95%
Equity Method Investee
Unconsolidated Real Estate Joint Venture Debt
Debt instrument, borrowing capacity	$ 668,250
Long-term Debt	$ 650,878

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