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Indebtedness (Details) |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2015 | Oct. 31, 2016 USD ($) property | Sep. 30, 2016 USD ($) property building note | Jul. 31, 2016 USD ($) building property | Apr. 30, 2016 USD ($) property | Feb. 29, 2016 USD ($) | Jan. 31, 2016 USD ($) property | Sep. 30, 2015 | Dec. 31, 2016 USD ($) note property | Sep. 30, 2016 USD ($) property building note | Sep. 30, 2015 USD ($) | Sep. 30, 2016 USD ($) property building note | Sep. 30, 2015 USD ($) | Nov. 03, 2016 USD ($) | Dec. 31, 2015 USD ($)
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, periodic payment, principal |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |  |
Number of public issues of unsecured senior notes | note |  |  | 6 |  |  |  |  |  |  | 6 |  | 6 |  |  |
Principal amount of unsecured senior notes |  |  | $ 1,722,032,000 |  |  |  |  |  |  | $ 1,722,032,000 |  | $ 1,722,032,000 |  |  | $ 1,478,536,000
Aggregate principal amount of mortgage debt |  |  | 1,160,847,000 |  |  |  |  |  |  | 1,160,847,000 |  | 1,160,847,000 |  |  |
Carrying value of mortgaged properties |  |  | 6,387,141,000 |  |  |  |  |  |  | 6,387,141,000 |  | 6,387,141,000 |  |  | 6,309,400,000
Proceeds from unsecured term loans |  |  |  |  |  |  |  |  |  |  |  | 0 | $ 200,000,000 |  |
Unsecured revolving credit facility |  |  | 215,000,000 |  |  |  |  |  |  | 215,000,000 |  | 215,000,000 |  |  | $ 775,000,000
Loss on early extinguishment of debt |  |  |  |  |  |  |  |  |  | (84,000) | $ (21,000) | (90,000) | (1,469,000) |  |
Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility, maximum borrowing capacity |  |  | 1,000,000,000 |  |  |  |  |  |  | 1,000,000,000 |  | 1,000,000,000 |  |  |
Option to increase the borrowing capacity under revolving credit facility |  |  | $ 1,500,000 |  |  |  |  |  |  | $ 1,500,000 |  | $ 1,500,000 |  |  |
Revolving credit facility, interest rate payable (as a percent) |  |  | 1.80% |  |  |  |  |  |  | 1.80% |  | 1.80% |  |  |
Interest expense and other associated costs incurred |  |  |  |  |  |  |  |  |  | $ 2,024,000 | $ 2,884,000 | $ 9,159,000 | $ 5,886,000 |  |
Unsecured revolving credit facility |  |  | $ 215,000,000 |  |  |  |  |  |  | $ 215,000,000 |  | $ 215,000,000 |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  | 1.80% | 1.50% | 1.70% | 1.50% |  |
Revolving credit facility, available amount |  |  | 785,000,000 |  |  |  |  |  |  | $ 785,000,000 |  | $ 785,000,000 |  |  |
Unsecured revolving credit facility | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate added to the base rate (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 1.30% |  |  |
Debt instrument, facility fee (as a percent) |  |  |  |  |  |  |  |  |  |  |  | 0.30% |  |  |
Senior unsecured notes due 2019 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | $ 400,000,000 |  |  |  |  |  |  | $ 400,000,000 |  | $ 400,000,000 |  |  |
Interest rate (as a percent) |  |  | 3.25% |  |  |  |  |  |  | 3.25% |  | 3.25% |  |  |
Senior unsecured notes 6.75% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | $ 200,000,000 |  |  |  |  |  |  | $ 200,000,000 |  | $ 200,000,000 |  |  |
Interest rate (as a percent) |  |  | 6.75% |  |  |  |  |  |  | 6.75% |  | 6.75% |  |  |
Unsecured senior notes due 2021 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | $ 300,000,000 |  |  |  |  |  |  | $ 300,000,000 |  | $ 300,000,000 |  |  |
Interest rate (as a percent) |  |  | 6.75% |  |  |  |  |  |  | 6.75% |  | 6.75% |  |  |
Senior unsecured notes due 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | $ 250,000,000 |  |  |  |  |  |  | $ 250,000,000 |  | $ 250,000,000 |  |  |
Interest rate (as a percent) |  |  | 4.75% |  |  |  |  |  |  | 4.75% |  | 4.75% |  |  |
Senior unsecured notes 5.625% due in 2042 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | $ 350,000,000 |  |  |  |  |  |  | $ 350,000,000 |  | $ 350,000,000 |  |  |
Interest rate (as a percent) |  |  | 5.625% |  |  |  |  |  |  | 5.625% |  | 5.625% |  |  |
Senior unsecured notes 6.25% due in 2046 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | $ 250,000,000 |  |  |  |  |  |  | $ 250,000,000 |  | $ 250,000,000 |  |  |
Interest rate (as a percent) |  |  | 6.25% |  |  | 6.25% |  |  |  | 6.25% |  | 6.25% |  |  |
Proceeds from unsecured term loans |  |  |  |  |  | $ 250,000,000 |  |  |  |  |  |  |  |  |
Term Loan Due 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 1.90% |  |  |  |  |  |  | 1.90% |  | 1.90% |  |  |
Unsecured term loan facility |  |  | $ 350,000,000 |  |  |  |  |  |  | $ 350,000,000 |  | $ 350,000,000 |  |  |
Interest expense and other associated costs incurred |  |  |  |  |  |  |  |  |  | $ 1,707,000 | $ 1,423,000 | $ 4,956,000 | $ 4,246,000 |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  | 1.90% | 1.60% | 1.90% | 1.60% |  |
Maximum borrowing capacity that may be increased |  |  | 700,000,000 |  |  |  |  |  |  | $ 700,000,000 |  | $ 700,000,000 |  |  |
Term Loan Due 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of unsecured senior notes |  |  | 200,000,000 |  |  |  |  |  |  | 200,000,000 |  | 200,000,000 |  |  |
Unsecured term loan facility |  |  | 200,000,000 |  |  |  |  |  |  | 200,000,000 |  | $ 200,000,000 |  |  |
Weighted average interest rate on debt (as a percent) | 2.30% |  |  |  |  |  |  |  |  |  |  | 2.30% |  |  |
Maximum borrowing capacity that may be increased |  |  | $ 400,000,000 |  |  |  |  |  |  | $ 400,000,000 |  | $ 400,000,000 |  |  |
Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  | 52 | 1 | 1 |  | 1 |  |  | 52 |  | 52 |  |  |
Number of buildings mortgaged | building |  |  | 54 |  |  |  |  |  |  | 54 |  | 54 |  |  |
Carrying value of mortgaged properties |  |  | $ 1,693,723,000 |  |  |  |  |  |  | $ 1,693,723,000 |  | $ 1,693,723,000 |  |  |
Weighted average interest rate on prepaid debt (as a percent) |  |  |  | 6.25% | 4.65% |  | 5.97% |  |  |  |  |  |  |  |
Prepayment of mortgage |  |  |  | $ 11,871,000 | $ 18,000,000 |  | $ 6,115,000 |  |  |  |  |  |  |  |
Capital leases |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Carrying value of mortgaged properties |  |  | $ 36,061,000 |  |  |  |  |  |  | $ 36,061,000 |  | $ 36,061,000 |  |  |
Number of properties recorded under capital lease | property |  |  | 2 |  |  |  |  |  |  | 2 |  | 2 |  |  |
Capital leases |  |  | $ 11,643,000 |  |  |  |  |  |  | $ 11,643,000 |  | $ 11,643,000 |  |  |
Unsecured Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  |  |  |  |  |  |  | 2.30% |  | 2.30% |  |  |
Unsecured Debt | LIBOR |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest rate added to the base rate (as a percent) |  |  |  |  |  |  |  | 1.80% |  |  |  | 1.40% |  |  |
Unsecured Debt September 2015 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense and other associated costs incurred |  |  |  |  |  |  |  |  |  | $ 1,173,000 | $ 33,000 | $ 3,433,000 | $ 33,000 |  |
Prepayment Notification | Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  | 2 |  |  |  |  |  |  | 2 |  | 2 |  |  |
Weighted average interest rate on prepaid debt (as a percent) |  |  | 5.92% |  |  |  |  |  |  |  |  |  |  |  |
Number of mortgage notes | note |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |
Prepayment of mortgage |  |  | $ 79,957,000 |  |  |  |  |  |  | $ 79,957,000 |  | $ 79,957,000 |  |  |
MOBs | Secured debt financing due 2026 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate principal amount of mortgage debt |  |  |  | $ 620,000,000 |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |
Number of buildings mortgaged | building |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on debt (as a percent) |  |  |  | 3.53% |  |  |  |  |  |  |  |  |  |  |
Scenario, Forecast | Prepayment Notification | Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |
Weighted average interest rate on prepaid debt (as a percent) |  |  |  |  |  |  |  |  | 5.86% |  |  |  |  |  |
Number of mortgage notes | note |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |
Prepayment of mortgage |  |  |  |  |  |  |  |  | $ 5,428,000 |  |  |  |  |  |
Subsequent Event | Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured revolving credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 265,000,000 |
Revolving credit facility, available amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 735,000,000 |
Subsequent Event | Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties mortgaged | property |  | 8 |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event | Prepayment Notification | Mortgages |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Indebtedness |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate on prepaid debt (as a percent) |  | 6.54% |  |  |  |  |  |  |  |  |  |  |  |  |
Prepayment of mortgage |  | $ 42,542,000 |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Represents the maximum borrowing capacity to which loan may be expanded per the terms of the agreement, at the option of the reporting entity. + References No definition available. + Details
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- Definition Weighted average interest rate on debt during the period. + References No definition available. + Details
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- Definition Represents the option to increase borrowings on the credit facility. + References No definition available. + Details
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- Definition Represents the number of public issues of unsecured senior notes. + References No definition available. + Details
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- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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=6877327&loc=d3e13212-122682 + Details
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- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629 + 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://www.xbrl.org/2003/role/presentationRef -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=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -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=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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=6876686&loc=d3e534808-122878 + Details
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