Summary of Significant Accounting Policies (Details 2) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Change in Accounting Estimate [Line Items] | |||
| Approximate amount by which basis of assets and liabilities for tax reporting purposes is lower than amount reported on consolidated balance sheet | $ 47 | ||
| Common Shares [Member] | |||
| Change in Accounting Estimate [Line Items] | |||
| Ordinary income (as a percent) | 83.10% | 86.50% | 48.00% |
| Return of capital (as a percent) | 16.90% | 13.50% | 52.00% |
| Preferred Shares [Member] | |||
| Change in Accounting Estimate [Line Items] | |||
| Ordinary income (as a percent) | 100.00% | 100.00% | |
| Return of capital (as a percent) | 0.00% | 0.00% | |
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- Definition Represents the approximate amount by which basis of assets and liabilities for tax reporting purposes are higher (lower) than the amount reported on consolidated balance sheet. No definition available.
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- Definition Represents the percentage of aggregate dividends declared during the period treated as ordinary income for federal tax purposes. No definition available.
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- Definition Represents the percentage of aggregate dividends declared during the period treated as return of capital for federal tax purposes. No definition available.
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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. No definition available.
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