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Indebtedness (Details) |  |  |  | 1 Months Ended | 3 Months Ended | 5 Months Ended | 7 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 20, 2020 $ / shares | May 21, 2020 $ / shares | Feb. 20, 2020 $ / shares | Jun. 30, 2020 USD ($) $ / shares | May 31, 2020 USD ($) property | Apr. 30, 2020 USD ($) | Feb. 29, 2020 USD ($) property | Sep. 30, 2020 USD ($) property | Sep. 30, 2019 USD ($) | Jun. 02, 2020 | Sep. 30, 2020 USD ($) property $ / shares | Sep. 30, 2020 USD ($) property | Sep. 30, 2019 USD ($) | Nov. 02, 2020 USD ($) | Dec. 31, 2019 USD ($)
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total real estate properties, gross |  |  |  |  |  |  |  | $ 7,371,731,000 |  |  | $ 7,371,731,000 | $ 7,371,731,000 |  |  | $ 7,461,586,000
Real estate property, accumulated depreciation |  |  |  |  |  |  |  | 1,651,864,000 |  |  | 1,651,864,000 | 1,651,864,000 |  |  | 1,570,801,000
Unsecured revolving credit facility |  |  |  |  |  |  |  | 0 |  |  | $ 0 | 0 |  |  | $ 537,500,000
Loss on early extinguishment of debt |  |  |  |  |  |  |  | $ 0 | $ 0 |  |  | $ 427,000 | $ 17,000 |  |
Dividend per share (in dollars per share) | $ / shares | $ 0.01 | $ 0.01 | $ 0.15 | $ 0.01 |  |  |  |  |  |  | $ 0.01 |  |  |  |
Joint Venture |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage |  |  |  |  |  |  |  | 55.00% |  |  | 55.00% | 55.00% |  |  |
LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate premium increase (as a percent) |  |  |  | 0.50% |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility, maximum borrowing capacity |  |  |  | $ 1,000,000,000 |  |  |  | $ 1,000,000,000 |  |  | $ 1,000,000,000 | $ 1,000,000,000 |  |  |
Line of credit facility, periodic payment, principal |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |
Revolving credit facility, interest rate payable (as a percent) |  |  |  |  |  |  |  | 2.60% |  |  | 2.60% | 2.60% |  |  |
Debt instrument, facility fee (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 0.30% |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  | 2.60% | 3.50% |  |  | 2.20% | 3.50% |  |
Unsecured revolving credit facility |  |  |  | 200,000,000 |  |  |  | $ 0 |  |  | $ 0 | $ 0 |  |  |
Revolving credit facility, available amount |  |  |  |  |  |  |  | 1,000,000,000 |  |  | 1,000,000,000 | 1,000,000,000 |  |  |
Unsecured revolving credit facility | Subsequent Event |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |
Revolving credit facility, available amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000,000 |
Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate principal amount of mortgage debt |  |  |  |  |  |  |  | $ 684,962,000 |  |  | $ 684,962,000 | $ 684,962,000 |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  | 7 |  |  | 7 | 7 |  |  |
Total real estate properties, gross |  |  |  |  |  |  |  | $ 946,037,000 |  |  | $ 946,037,000 | $ 946,037,000 |  |  |
Mortgages | Joint Venture |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate principal amount of mortgage debt |  |  |  |  |  |  |  | $ 620,000,000 |  |  | $ 620,000,000 | $ 620,000,000 |  |  |
Ownership percentage |  |  |  |  |  |  |  | 55.00% |  |  | 55.00% | 55.00% |  |  |
Finance Leases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  | 2 |  |  | 2 | 2 |  |  |
Total real estate properties, gross |  |  |  |  |  |  |  | $ 35,611,000 |  |  | $ 35,611,000 | $ 35,611,000 |  |  |
Lease obligations |  |  |  |  |  |  |  | 8,084,000 |  |  | 8,084,000 | 8,084,000 |  |  |
Real estate property, accumulated depreciation |  |  |  |  |  |  |  | 17,429,000 |  |  | 17,429,000 | 17,429,000 |  |  |
Term loan due 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  | 200,000,000 |  |  |  | $ 200,000,000 |  |  | $ 200,000,000 | $ 200,000,000 |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  | 2.70% | 3.60% |  |  | 2.70% | 3.80% |  |
Interest rate (as a percent) |  |  |  |  |  |  |  | 2.80% |  |  | 2.80% | 2.80% |  |  |
Term loan due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  | 250,000 |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  | 2.40% |  |  |  |  |
Loss on early extinguishment of debt |  |  |  |  |  |  |  |  |  |  |  | $ 26,000 |  |  |
Senior Unsecured Note Due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  | 6.75% |  |  |  |  |  |  |  |  |
Principal amount plus accrued and unpaid interest |  |  |  |  |  | $ 200,000,000 |  |  |  |  |  |  |  |  |
Unpaid interest |  |  |  |  |  | $ 6,750,000 |  |  |  |  |  |  |  |  |
Mortgage 7.49 Percent Due January 2022 | Medical Office Buildings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  | 7.49% |  |  |  |  |  |  |  |  |  |
Number of properties | property |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |
Repayments of debt |  |  |  |  | $ 1,213,000 |  |  |  |  |  |  |  |  |  |
Loss on early extinguishment of debt |  |  |  |  |  |  |  |  |  |  |  | 155,000 |  |  |
Senior Unsecured Note Due March 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  | $ 1,000,000,000 |  |  |  | $ 1,000,000,000 |  |  | $ 1,000,000,000 | 1,000,000,000 |  |  |
Interest rate (as a percent) |  |  |  | 9.75% |  |  |  |  |  |  |  |  |  |  |
Proceeds from debt |  |  |  | $ 982,300,000 |  |  |  |  |  |  |  |  |  |  |
Redemption percentage, maximum |  |  |  | 40.00% |  |  |  |  |  |  |  |  |  |  |
Outstanding percentage, maximum |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |
Senior Unsecured Note Due March 2026 | Life Science Building |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  |  |  |  |  | 6.25% |  |  |  |  |  |  |  |
Number of properties | property |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |
Repayments of debt |  |  |  |  |  |  | $ 1,554,000 |  |  |  |  |  |  |  |
Loss on early extinguishment of debt |  |  |  |  |  |  |  |  |  |  |  | 246,000 |  |  |
Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  |  |  |  |  | 2,650,000,000 |  |  | 2,650,000,000 | 2,650,000,000 |  |  |
Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt face amount |  |  |  |  |  |  |  | $ 200,000,000 |  |  | $ 200,000,000 | $ 200,000,000 |  |  |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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