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Equity Distribution Program (Details) - Equity Distribution Program - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Mar. 31, 2019
Class of Stock [Line Items] |  |
Equity distribution program, maximum amount authorized |  | $ 500,000,000.0
Sales of common stock under the equity distribution program | $ 0 |

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- Definition Stock Issuable, Value, Maximum + References No definition available. + Details
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Balance Type: | credit
Period Type: | instant

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
Period Type: | duration

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- Definition The cash inflow from the additional capital contribution to the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 + Details
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Balance Type: | debit
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |