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Debt | 9 Months Ended
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Sep. 30, 2018
Debt [Abstract] |
Debt Disclosure [Text Block] | 5. Debt Credit Facility On April 24, 2017, Boston Properties Limited Partnership amended and restated its unsecured revolving credit agreement (as amended and restated, the "2017 Credit Facility"). Among other things, the 2017 Credit Facility (1) increased the total commitment of the revolving line of credit (the "Revolving Facility") from $1.0 billion to $1.5 billion, (2) extended the maturity date from July 26, 2018 to April 24, 2022, (3) reduced the per annum variable interest rates, and (4) added a $500.0 million delayed draw term loan facility (the "Delayed Draw Facility") that permits Boston Properties Limited Partnership to draw until the first anniversary of the closing date. Based on Boston Properties Limited Partnership’s current credit rating, (1) the applicable Eurocurrency margins for the Revolving Facility and Delayed Draw Facility are 82.5 basis points and 90 basis points, respectively, and (2) the facility fee on the Revolving Facility commitment is 0.125% per annum. On April 24, 2018, Boston Properties Limited Partnership exercised its option to draw $500.0 million on its Delayed Draw Facility. The Delayed Draw Facility bears interest at a variable rate equal to LIBOR plus 0.90% per annum based on Boston Properties Limited Partnership's current credit rating and matures on April 24, 2022. As of September 30, 2018, Boston Properties Limited Partnership had $500.0 million of borrowings outstanding under its Delayed Draw Facility, $170.0 million of borrowings outstanding under its Revolving Facility and outstanding letters of credit totaling approximately $0.3 million, with the ability to borrow approximately $1.3 billion.

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- Definition The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 + Details
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