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Noncontrolling Interests - Holders of Convertible Limited Partnership Units in the Operating Partnership - Additional Information (Detail) - shares | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Noncontrolling Interests |  |  |
Noncontrolling Interest [Line Items] |  |  |
Limited partnership units (in shares) | 7,938,495 |  |
Limited partnership units, conversion ratio | 1 |  |
Outstanding stock percent that should be acquired for rights to be exercised | 39.90% |  |
Limited partnership units convertible to shares of common stock, eligible for conversion (in shares) | 1,947,000 |  |
Fully converted partnership units and diluted weighted average shares outstanding (in shares) | 31,300,000 | 30,900,000 | 30,200,000
Saul Holdings Limited Partnership |  |  |
Noncontrolling Interest [Line Items] |  |  |
Percentage of ownership in operating partnership | 74.60% |  |
Saul Holdings Limited Partnership | Noncontrolling Interests |  |  |
Noncontrolling Interest [Line Items] |  |  |
Percentage of ownership interest of noncontrolling interest | 25.40% |  |

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- Definition Limited Partners' Capital Account, Convertible Units, Conversion Ratio + References No definition available. + Details
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- Definition Limited Partners' Capital Account, Convertible Units, Eligible for Conversion + References No definition available. + Details
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- Definition Minimum Outstanding Stock Percentage That Should be Acquired for Rights Issued to Become Exercisable + References No definition available. + Details
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- Definition Partners' Capital Account, Units, Converted and Weighted Average Shares Outstanding, Diluted + References No definition available. + Details
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- Definition Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055 + Details
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- Definition The number of limited partner units outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 5 -Subparagraph (SAB Topic 4.F) -URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770 + Details
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