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v3.19.3

Borrowings - Additional Information (Details) | 1 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Aug. 31, 2019 USD ($) | May 31, 2019 USD ($) | Mar. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) Loan | Dec. 31, 2018 USD ($)
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 3.80% |
Individual property mortgages |  |  |  | $ 645,406,000 | $ 475,026,000
Unsecured Debt [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 3.70% |
Number of Term Loans | Loan |  |  |  | 2 |
Unsecured Debt [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Maturity Date |  |  |  | Mar. 01, 2026 |
Debt Instrument, Face Amount |  |  |  | $ 3,192,000,000 |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 3.90% |
Unsecured Debt [Member] | KeyBank Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount |  |  |  | $ 150,000,000.0 |
Number of Term Loans | Loan |  |  |  | 1 |
Debt Instrument Maturity Year |  |  |  | 2021 |
Unsecured Debt [Member] | Wells Fargo Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount |  |  |  | $ 300,000,000.0 |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 2.32% |
Number of Term Loans | Loan |  |  |  | 1 |
Debt Instrument Maturity Year |  |  |  | 2022 |
Debt Instrument Maturity Period |  |  |  | 2020-01 |
Repayments of Unsecured Debt |  | $ 300,000,000.0 |  |  |
Unsecured Debt [Member] | US Bank Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Repayments of Unsecured Debt | $ 150,000,000.0 |  |  |  |
Secured Debt [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 4.60% |
Secured Debt [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Maturity Date |  |  |  | Oct. 03, 2036 |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 4.60% |
Individual property mortgages |  |  |  | $ 648,800,000 |
Secured Debt [Member] | Mortgage Maturing in February 2049 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 4.43% |
Proceeds from Loan Originations |  |  |  | $ 191,300,000 |
Secured Debt [Member] | Mortgages [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Repayments of Secured Debt | 13,200,000 |  |  |  |
M A A L P | Commercial Paper Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Payment Terms |  | 397 |  |  |
Debt Instrument, Face Amount |  |  |  | $ 200,000,000.0 |
M A A L P | Unsecured Debt [Member] | Years to Maturity [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Term |  |  |  | 6 years 4 months 24 days |
M A A L P | Unsecured Debt [Member] | $1 Billion Unsecured Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Line of Credit Facility, Current Borrowing Capacity |  | $ 1,000,000,000.0 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | $ 1,500,000,000 |  |  |
Debt Instrument, Maturity Date |  | May 31, 2023 |  |  |
Line of Credit Facility, Amount Outstanding |  |  |  | $ 0 |
Letters of Credit Outstanding, Amount |  |  |  | 2,800,000 |
M A A L P | Unsecured Debt [Member] | Public Income Notes [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount |  |  |  | 3,000,000,000.0 |
M A A L P | Unsecured Debt [Member] | Private Placement [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount |  |  |  | 242,000,000.0 |
M A A L P | Unsecured Debt [Member] | Private Placement [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount |  |  |  | $ 242,000,000.0 |
M A A L P | Unsecured Debt [Member] | 3.95% Initial Notes Due 2029 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Payment Terms |  |  | Interest on the Initial 2029 Notes is payable on March 15 and September 15 of each year, beginning on September 15, 2019. |  |
Debt Instrument, Face Amount |  |  | $ 300,000,000.0 |  |
Debt Instrument, Term |  |  | 10 years |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 3.95% |  |
Debt Instrument, Redemption Price, Percentage |  |  | 99.72% |  |
Debt Issuance Costs, Gross |  |  | $ 2,800,000 |  |
Proceeds from Debt, Net of Issuance Costs |  |  | 297,200,000 |  |
Settlement of Forward Swaps |  |  | $ 300,000,000.0 |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  | 4.24% |  |
M A A L P | Unsecured Debt [Member] | 3.95% Additional Notes due 2029 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 250,000,000.0 |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.95% |  |  |  |
M A A L P | Unsecured Debt [Member] | 2.985% Notes due 2029 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Redemption Price, Percentage | 107.827% |  |  |  |
Debt Issuance Costs, Gross | $ 22,100,000 |  |  |  |
Proceeds from Debt, Net of Issuance Costs | $ 272,100,000 |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage | 2.985% |  |  |  |
Minimum [Member] | Unsecured Debt [Member] | KeyBank Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  | 0.90% |
Minimum [Member] | Unsecured Debt [Member] | Wells Fargo Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  | 0.90% |
Minimum [Member] | M A A L P | Unsecured Debt [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Term |  |  |  | 7 years |
Minimum [Member] | M A A L P | Unsecured Debt [Member] | $1 Billion Unsecured Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 0.75% |  |  |
Maximum [Member] | Unsecured Debt [Member] | KeyBank Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  | 1.75% |
Maximum [Member] | Unsecured Debt [Member] | Wells Fargo Term Loan [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  |  | 1.75% |
Maximum [Member] | M A A L P | Commercial Paper Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Face Amount |  | $ 500,000,000.0 |  |  |
Maximum [Member] | M A A L P | Unsecured Debt [Member] | Fixed Rate Debt Senior Notes [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Term |  |  |  | 12 years |
Maximum [Member] | M A A L P | Unsecured Debt [Member] | $1 Billion Unsecured Revolving Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 1.45% |  |  |

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