Stockholders' Equity Schedule of Common Dividends Declared (Details) - $ / shares |
3 Months Ended | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Nov. 01, 2017 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
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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 | Dec. 14, 2017 | Sep. 14, 2017 | Jun. 15, 2017 | Mar. 14, 2017 | Dec. 15, 2016 | Sep. 15, 2016 | Jun. 16, 2016 | Mar. 15, 2016 | Dec. 16, 2015 | Sep. 16, 2015 | Jun. 17, 2015 | Mar. 18, 2015 | |
| Record Date | Dec. 26, 2017 | Sep. 29, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 30, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 30, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | |
| Payment Date | Dec. 29, 2017 | Oct. 27, 2017 | Jul. 27, 2017 | Apr. 27, 2017 | Jan. 27, 2017 | Oct. 20, 2016 | Jul. 20, 2016 | Apr. 21, 2016 | Jan. 20, 2016 | Oct. 22, 2015 | Jul. 21, 2015 | Apr. 21, 2015 | |
| Dividends declared per common share (in usd per share) | $ 0.47 | $ 0.52 | $ 0.52 | $ 0.5 | $ 0.48 | $ 0.46 | $ 0.46 | $ 0.46 | $ 0.52 | $ 0.52 | $ 0.52 | $ 0.52 | |
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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://www.xbrl.org/2003/role/presentationRef
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- Definition Date the declared dividend will be paid, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Date the dividend to be paid was declared, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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