Stockholders' Equity Schedule of Common Dividends Declared (Details) - $ / shares |
1 Months Ended | 2 Months Ended | 3 Months Ended | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Nov. 01, 2017 |
Jul. 31, 2018 |
Sep. 30, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
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| Class of Stock [Line Items] | ||||||||||||||
| Number of shares of common stock of Granite Point Mortgage Trust Inc distributed via special dividend (in shares) | 33,100,000 | |||||||||||||
| Common Stock [Member] | ||||||||||||||
| Class of Stock [Line Items] | ||||||||||||||
| Declaration Date | Jul. 13, 2018 | Dec. 18, 2018 | Sep. 20, 2018 | Jun. 19, 2018 | Mar. 20, 2018 | Dec. 14, 2017 | Sep. 14, 2017 | Jun. 15, 2017 | Mar. 14, 2017 | Dec. 15, 2016 | Sep. 15, 2016 | Jun. 16, 2016 | Mar. 15, 2016 | |
| Record Date | Jul. 25, 2018 | Dec. 31, 2018 | Oct. 01, 2018 | Jun. 29, 2018 | Apr. 02, 2018 | Dec. 26, 2017 | Sep. 29, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 30, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | |
| Payment Date | Jul. 30, 2018 | Jan. 28, 2019 | Oct. 29, 2018 | Jul. 27, 2018 | Apr. 27, 2018 | Dec. 29, 2017 | Oct. 27, 2017 | Jul. 27, 2017 | Apr. 27, 2017 | Jan. 27, 2017 | Oct. 20, 2016 | Jul. 20, 2016 | Apr. 21, 2016 | |
| Dividends declared per common share (in usd per share) | $ 0.158370 | $ 0.470000 | $ 0.311630 | $ 0.470000 | $ 0.470000 | $ 0.470000 | $ 0.520000 | $ 0.520000 | $ 0.500000 | $ 0.480000 | $ 0.460000 | $ 0.460000 | $ 0.460000 | |
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- Definition Special dividend distributed to shareholders during the period. 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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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Date the declared dividend will be paid, in CCYY-MM-DD format. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Date the dividend to be paid was declared, in CCYY-MM-DD format. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format. No definition available.
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- Details
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