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Equity - Narrative (Details) |  |  |  |  |  | 3 Months Ended | 12 Months Ended | 42 Months Ended | 77 Months Ended | 80 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 25, 2021 USD ($) shares | Mar. 01, 2021 shares | Jan. 22, 2021 USD ($) shares | Jan. 15, 2020 USD ($) shares | May 01, 2019 USD ($) shares | Mar. 31, 2021 USD ($) vote $ / shares shares | Mar. 31, 2020 USD ($) $ / shares shares | Dec. 31, 2019 shares | Sep. 30, 2019 USD ($) shares | Dec. 31, 2020 USD ($) shares | Mar. 31, 2021 USD ($) vote shares | Dec. 31, 2020 USD ($) $ / shares shares | Mar. 31, 2021 USD ($) vote shares | Oct. 29, 2020 shares | Jul. 17, 2020 USD ($) | Feb. 26, 2020 USD ($) | Apr. 30, 2019 shares | Jun. 30, 2015 shares
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 323,881,102 |  |  |  | 230,320,668 | 323,881,102 | 230,320,668 | 323,881,102 |  |  |  |  |
Proceeds from sale of shares | $ |  |  |  |  |  |  |  |  |  |  |  | $ 2,800,000,000 |  |  |  |  |  |  |
Shares issued | $ | [1] |  |  |  |  |  | $ 324,000 |  |  |  | $ 230,000 | 324,000 | $ 230,000 | $ 324,000 |  |  |  |  |
Share Redemption Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum ownership balance (shares) | $ |  |  |  |  |  |  | $ 2,500 |  |  |  |  | 2,500 |  | 2,500 |  |  |  |  |
Minimum holding period for stock to be redeemed from stockholder by the Company |  |  |  |  |  |  | 1 year |  |  |  |  |  |  |  |  |  |  |  |
Distribution Reinvestment Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock authorized under offering (shares) | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,000,000 | $ 200,000,000 |  |
Period for written notice |  |  |  |  |  |  | 10 days |  |  |  |  |  |  |  |  |  |  |  |
Shares issued | $ |  |  |  |  |  |  | $ 325,400,000 |  |  |  | $ 318,200,000 | 325,400,000 | $ 318,200,000 | 325,400,000 |  |  |  |  |
Follow-on Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock authorized under offering (shares) | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,200,000,000 |  |
Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued (shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 43,772,611
Stock authorized under offering (shares) | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,000,000,000.0 |  |
Maximum | Share Redemption Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate redemption of Company's shares (percent) |  |  |  |  |  |  | 5.00% |  |  | 5.00% |  |  |  |  |  |  |  |  |
RSUs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
RSU's issued (in shares) |  |  |  |  |  |  | 1,619,255 |  |  |  | 589,248 |  |  |  |  |  |  |  |
Share-based Payment Arrangement, Expense | $ |  |  |  |  |  |  | $ 1,700,000 | $ 1,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Shares used to satisfy employee tax withholding requirements on vesting restricted stock (shares) |  |  |  |  |  |  | 83,027 |  |  |  |  |  |  |  |  |  |  |  |
RSUs | 2019 Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
RSU's issued (in shares) |  |  |  |  |  | 1,009,415 |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting installment (percent) |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of grants issued | $ |  |  |  |  |  | $ 9,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized cost | $ |  |  |  |  |  |  | $ 3,900,000 |  |  |  |  | 3,900,000 |  | 3,900,000 |  |  |  |  |
Unrecognized cost recognition period |  |  |  |  |  |  | 2 years |  |  |  |  |  |  |  |  |  |  |  |
RSUs | 2020 Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
RSU's issued (in shares) |  |  |  |  | 589,248 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of grants issued | $ |  |  |  |  | $ 5,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized cost | $ |  |  |  |  |  |  | $ 3,000,000.0 |  |  |  |  | 3,000,000.0 |  | 3,000,000.0 |  |  |  |  |
Unrecognized cost recognition period |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |
Vesting (percent) |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
RSUs | 2021 Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
RSU's issued (in shares) |  | 547,908 |  | 1,071,347 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of grants issued | $ |  | $ 4,900,000 |  | $ 9,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized cost | $ |  |  |  |  |  |  | $ 7,700,000 |  |  |  |  | $ 7,700,000 |  | $ 7,700,000 |  |  |  |  |
Unrecognized cost recognition period |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |
Restricted Stock | Former directors |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
RSU's issued (in shares) |  |  | 3,901 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Class T |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 560,462 |  |  |  |  | 560,462 |  | 560,462 |  |  |  |  |
Common Class S |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 1,800 |  |  |  |  | 1,800 |  | 1,800 |  |  |  |  |
Common Class D |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 41,396 |  |  |  |  | 41,396 |  | 41,396 |  |  |  |  |
Common Class I |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 1,902,061 |  |  |  |  | 1,902,061 |  | 1,902,061 |  |  |  |  |
Common Class A |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 24,415,356 |  |  |  |  | 24,415,356 |  | 24,415,356 |  |  |  |  |
Common Class AA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 47,432,524 |  |  |  |  | 47,432,524 |  | 47,432,524 |  |  |  |  |
Common Class AAA |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 920,743 |  |  |  |  | 920,743 |  | 920,743 |  |  |  |  |
Common Class E |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of votes each share is entitled to | vote |  |  |  |  |  |  | 1 |  |  |  |  | 1 |  | 1 |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 248,606,760 |  |  |  |  | 248,606,760 |  | 248,606,760 |  |  |  |  |
Common Class E | 2021 Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares contingently entitled to be received for each RSU (shares) |  | 1 |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Class E | Share Redemption Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Excess of quarterly cap limitation (in shares) |  |  |  |  |  |  |  |  |  | 2,872,488 |  |  |  |  |  |  |  |  |
Excess of quarterly cap limitation | $ |  |  |  |  |  |  |  |  |  | $ 27,400,000 |  |  |  |  |  |  |  |  |
Percentage of redemption requests not redeemed (percent) |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |  |  |  |  |  |
Common Class E | Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued (shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 93,457,668 |  |  | 174,981,547 |
Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares outstanding (in shares) |  |  |  |  |  |  | 323,881,102 | 229,671,555 | 227,853,720 |  | 230,320,668 | 323,881,102 | 230,320,668 | 323,881,102 |  |  |  |  |
Stock redeemed during period (in shares) |  |  |  |  |  |  | 772,265 | 548,312 |  |  |  |  |  |  |  |  |  |  |
Weighted average price per share (in dollars per share) | $ / shares |  |  |  |  |  |  | $ 8.96 | $ 9.32 |  |  |  |  |  |  |  |  |  |  |
Shares used to satisfy employee tax withholding requirements on vesting restricted stock (shares) |  |  |  |  |  |  | 99,298 |  |  |  |  |  |  |  |  |  |  |  |
Common Stock | Share Redemption Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock redeemed during period (in shares) |  |  |  |  |  |  | 771,109 |  |  |  |  |  |  | 26,844,716 |  |  |  |  |
Stock redeemed, value | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 252,200,000 |  |  |  |  |  |
Weighted average price per share (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.40 |  |  |  |  |  |
Common Stock | Common Class E | RSUs | 2020 Restricted Stock Units |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares contingently entitled to be received for each RSU (shares) |  |  |  |  | 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | See Note 9, Equity, for the number of shares outstanding of each class of common stock as of March 31, 2021.

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