Summary of Significant Accounting Policies and Basis of Presentation (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Schedule of Recent Accounting Standards

Recent Accounting Standards

Standards Adopted

Standard/Description	Effective Date and Adoption Considerations	Effect on Financial Statements or Other significant Matters
Accounting Standards Update (“ASU”) 2017-12, Derivatives and Hedging:Targeted Improvements to Accounting for Hedging Activities. This standard better aligns a company’s financial reporting for hedging activities with the economic objectives of those activities.	We adopted the standard as of January 1, 2018.	The adoption of the new standard did not have a material impact on our consolidated financial statements.
ASU 2017-09, Compensation - Stock Compensation (Topic 718) - Scope of Modification Accounting. This standard provides guidance about which changes to the terms or conditions of a share-based payment award require an entity to apply modification accounting.	We adopted the standard as of January 1, 2018.	The adoption of the new standard did not have a material impact on our consolidated financial statements.
ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments. This standard provides specific guidance on how cash receipts and payments should be presented and classified in the statement of cash flows for eight specific issues.	We adopted the standard as of January 1, 2018.	The adoption of the new standard did not have a material impact on our consolidated financial statements.

Standard/Description	Effective Date and Adoption Considerations	Effect on Financial Statements or Other significant Matters
ASU 2016-01, Recognition and Measurement of Financial Assets and Liabilities. This standard eliminates the requirement for public entities to disclose the methods and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet.	We adopted the standard as of January 1, 2018.	The adoption of the new standard did not have a material impact on our consolidated financial statements.
ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). This standard provides accounting guidance for all revenue arising from contracts with customers and affects all entities that enter into contracts to provide goods or services to their customers (unless the contracts are in the scope of other GAAP requirements, such as the leasing literature). The guidance also provides a model for the measurement and recognition of gains and losses on the sale of certain nonfinancial assets, such as property and equipment, including real estate.	We adopted the standard as of January 1, 2018.	We evaluated the requirements for recognition of revenue from contracts with customers and measuring gains and losses on the sale of properties in accordance with ASU 2014-09 and concluded the adoption of the new standard did not impact in any material respect the amount or timing of our revenue recognition.

Standards Not Yet Adopted

Standard/Description	Effective Date and Adoption Considerations	Effect on Financial Statements or Other significant Matters
ASU 2016-02, Leases (Topic 842). This standard amends existing lease accounting standards for both lessees and lessors. Lessees must classify most leases as either finance or operating leases. For lease contracts, or contracts with an embedded lease, with a duration of more than one year in which we are the lessee, the present value of future lease payments are recognized on our consolidated balance sheets as a right-of-use asset and a corresponding lease liability. Lessors Lease contracts currently classified as operating leases are accounted for similarly to existing guidance. However, lessors are required to account for each lease and non-lease component, such as common area maintenance or tenant service revenues, of a contract separately. In July 2018, the FASB issued 2018-11, Leases (Topic 842) - Targeted Improvements (“ASU 2018-11”), which provides lessors optional transition relief from implementing this aspect of ASU 2016-02 if the following criteria are met: (1) both components have the same timing and pattern of revenue and (2) if accounted for separately, both components would be classified as an operating lease. Also under ASU 2016-02, only incremental costs or initial direct costs of executing a lease contract qualify for capitalization, while prior accounting standards allowed for the capitalization of indirect leasing costs.	We adopted the new standard as of January 1, 2019.	Lessees We have evaluated lease contracts where we are the lessee to determine the impact they have on Washington REIT’s consolidated financial statements, and have determined that adoption of the new standard as of January 1, 2019 did not have a material impact on our consolidated financial statements. Lessors The leases for which we are lessor meet both criteria for relief under ASU 2018-11 and we elected not to bifurcate lease contracts into lease and non-lease components. Accordingly, both lease and non-lease components will be presented in “Real estate rental revenue” in our consolidated financial statements subsequent to adoption. Transition Under ASU 2018-11, the FASB offered optional transition relief, if elected as a package, and applied consistently by an entity to all of its leases. Accordingly, upon adoption we elected, as a package, the practical expedients for all leases as follows: (1) we will not reassess whether any expired or existing contracts are or contain leases, (2) we will not reassess the lease classification for any expired or existing leases and (3) we will not reassess initial direct costs for any existing leases. Under ASU 2016-02, entities are required to implement the standard as of the beginning of the earliest comparative period presented or January 1, 2017 for calendar-year public business entities. Under ASU 2018-11, the FASB offered optional transition relief that permits entities to continue to apply ASC 840, including its disclosure requirements, in the comparative periods presented in the year of adoption. Accordingly, we made a policy election to apply ASC 840 to comparative periods beginning on January 1, 2019.
ASU 2016-13, Measurement of Credit Losses on Financial Instruments. This standard requires financial assets measured at an amortized cost basis, including trade receivables, to be presented at the net amount expected to be collected.	The new standard is effective for public entities for fiscal years beginning after December 15, 2019 and for interim periods therein, with adoption one year earlier permitted.	We are currently evaluating the impact the new standard may have on our consolidated financial statements.
ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software. This standard requires a customer in a cloud computing arrangement that is a service contract to follow the internal-use software guidance to determine which implementation costs to capitalize as assets.	The standard is effective for public entities for fiscal years beginning after December 31, 2019 and for interim periods therein, with early adoption permitted.	We are currently evaluating the impact the new standard may have on our consolidated financial statements.

Schedule of Interest and Interest Capitalized

Interest expense and interest capitalized to real estate assets related to development and major renovation activities for the three years ended December 31, 2018 were as follows (in thousands):

	Year Ended December 31,
	2018			2017			2016
Total interest incurred	$	53,235		$	48,498		$	53,794
Capitalized interest	(2,091		)	(964		)	(668		)
Interest expense, net of capitalized interest	$	51,144		$	47,534		$	53,126