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Summary of Significant Accounting Policies - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 USD ($) tenant store shares | Dec. 31, 2017 USD ($) shares | Dec. 31, 2016 USD ($) shares | Dec. 31, 2015 USD ($)
Significant Accounting Policies [Line Items] |  |  |  |
Number of shopping centers | store | 32 |  |  |
Capitalized interest | $ (6,222,000) | $ (3,489,000) | $ (2,527,000) |
Depreciation and amortization of deferred leasing costs | 39,768,000 | 40,197,000 | 38,755,000 |
Repairs and maintenance expense | 11,900,000 | 11,600,000 | 11,800,000 |
Deferred leasing costs, net | 28,083,000 | 27,255,000 |  |
Accumulated amortization deferred leasing cost | 37,700,000 | 35,300,000 |  |
Amortization expense deferred leasing cost | 6,100,000 | 5,500,000 | 5,600,000 |
Allowance for doubtful accounts receivables | 559,000 | 405,000 | 1,958,000 | $ 1,263,000
Accounts receivable, net representing rental income accrued | 43,300,000 | 44,100,000 |  |
Allowance for doubtful accounts receivables representing rental income accrued | 100,000 | 200,000 |  |
Deferred debt costs, net of accumulated amortization | 10,343,000 | 6,900,000 |  |
Accumulated amortization | 7,300,000 | 8,200,000 |  |
Accrued penalties and interest | 0 | 0 | $ 0 |
Tax basis of the company's real estate investments | $ 1,350,000,000 | $ 1,320,000,000 |  |
Shares issued to directors (in shares) | shares | 43,150 | 152,758 | 251,323 |
Shares issued to directors | $ 1,558,000 | $ 1,448,000 | $ 1,348,000 |
Capitalized lease costs | $ 2,100,000 |  |  |
Director |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Shares credited to deferred fee accounts (in shares) | shares | 114,644 |  |  |
Shares issued to directors (in shares) | shares | 200 | 200 | 200 |
Shares issued to directors | $ 108,800 | $ 130,700 | $ 150,100 |
Minimum | Building |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Estimated useful life | 35 years |  |  |
Maximum | Building |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Estimated useful life | 50 years |  |  |
Maximum | Building Improvements |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Estimated useful life | 20 years |  |  |
Revenue |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Number of tenants | tenant | 2 |  |  |
Revenue | Minimum |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Percentage of total revenue | 2.50% |  |  |
Revenue | Giant Food |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Percentage of total revenue | 4.70% |  |  |
Number of shopping centers | store | 10 |  |  |
Revenue | Capital One |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Percentage of total revenue | 2.70% |  |  |
Number of shopping centers | store | 17 |  |  |
Glebe Road Construction Loan |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Deferred debt costs, net of accumulated amortization | $ 1,800,000 |  |  |
Saul Holdings Limited Partnership |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Percentage of ownership in operating partnership | 74.30% |  |  |

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- Definition For an unclassified balance sheet, the accumulated amortization, as of the reporting date, which represents the periodic charge to earnings of initial direct costs which have been deferred and are being allocated over the lease term in proportion to the recognition of rental income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=77913719&loc=d3e40879-112712 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=77902619&loc=d3e40588-112709 + Details
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