Mortgage Notes Payable, Credit Facilities and Senior Notes Mortgage Notes Payable, Credit Facility and Senior Notes - Principal Repayments of Unsecured Senior Notes (Details) - Senior Notes	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
2020	$ 0
2021	0
2022	0
2023	250,000,000
2024	250,000,000
Thereafter	450,000,000
Total	$ 950,000,000

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 30
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
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