Indebtedness	3 Months Ended
Mar. 31, 2016
Indebtedness
Indebtedness	Note 6. Indebtedness Our principal debt obligations at March 31, 2016 were: (1) our $230,000 of outstanding borrowings under our $1,000,000 unsecured revolving credit facility; (2) our $400,000 unsecured term loan; (3) an aggregate outstanding principal amount of $2,900,000 of public issuances of unsecured senior notes; and (4) our public issuance of $8,478 outstanding principal amount of convertible senior notes. Our $1,000,000 unsecured revolving credit facility is available for general business purposes, including acquisitions. The maturity date of our unsecured revolving credit facility is July 15, 2018 and, subject to the payment of an extension fee and meeting other conditions, we have the option to extend the stated maturity date of our unsecured revolving credit facility by one year to July 15, 2019. We can borrow, repay and reborrow funds available under our unsecured revolving credit facility until maturity, and no principal repayment is due until maturity. We are required to pay interest on borrowings under our unsecured revolving credit facility at an annual rate of LIBOR plus a premium, which was 110 basis points as of March 31, 2016. We also pay a facility fee on the total amount of lending commitments, which was 20 basis points per annum at March 31, 2016 under our unsecured revolving credit facility. Both the interest rate premium and the facility fee are subject to adjustment based upon changes to our credit ratings. As of March 31, 2016, the annual interest rate for the amount outstanding under our unsecured revolving credit facility was 1.53%. The weighted average annual interest rate for borrowings under our unsecured revolving credit facility was 1.53% and 1.27% for the three months ended March 31, 2016 and 2015, respectively. As of March 31, 2016 and May 9, 2016, we had $230,000 and $139,000 outstanding under our unsecured revolving credit facility, respectively. Our $400,000 unsecured term loan, which matures on April 15, 2019, is prepayable without penalty at any time. We are required to pay interest on the amounts under our unsecured term loan at a rate of LIBOR plus a premium, which was 120 basis points as of March 31, 2016. The interest rate premium is subject to adjustment based on changes to our credit ratings. As of March 31, 2016, the annual interest rate for the amount outstanding under our unsecured term loan was 1.64%. The weighted average annual interest rate for borrowings under our unsecured term loan was 1.62% and 1.37% for the three months ended March 31, 2016 and 2015, respectively. Our credit agreement for our unsecured revolving credit facility and unsecured term loan also includes a feature under which maximum aggregate borrowings may be increased up to $2,300,000 on a combined basis in certain circumstances. Our credit agreement for our unsecured revolving credit facility and unsecured term loan and our unsecured notes indentures and their supplements provide for acceleration of payment of all amounts outstanding upon the occurrence and continuation of certain events of default, such as, in the case of our credit agreement, a change of control of us, which includes The RMR Group LLC, or RMR LLC, ceasing to act as our business manager. Our credit agreement for our unsecured revolving credit facility and unsecured term loan and our senior unsecured notes indentures and their supplements also contain a number of covenants, including covenants that restrict our ability to incur debts or to make distributions under certain circumstances and generally require us to maintain certain financial ratios. We believe we were in compliance with the terms and conditions of our credit agreement for our unsecured revolving credit facility and unsecured term loan and our senior unsecured notes indentures and their supplements at March 31, 2016. On February 3, 2016, we issued $750,000 aggregate principal amount of unsecured senior notes in public offerings, which included $400,000 aggregate principal amount of 4.25% unsecured senior notes due 2021 and $350,000 aggregate principal amount 5.25% unsecured senior notes due 2026. Net proceeds from these offerings were $731,523 after original issue discounts and offering expenses. On March 11, 2016, we redeemed at par all of our outstanding 6.30% senior notes due 2016 for $275,000 and unpaid interest (an aggregate of $279,139) using cash on hand and borrowings under our unsecured revolving credit facility. As a result of the redemption, we recorded a loss on early extinguishment of debt of $70 in the three months ended March 31, 2016 which represented the unamortized discounts and issuance costs of these notes.

Note 6. Indebtedness

Our principal debt obligations at March 31, 2016 were: (1) our $230,000 of outstanding borrowings under our $1,000,000 unsecured revolving credit facility; (2) our $400,000 unsecured term loan; (3) an aggregate outstanding principal amount of $2,900,000 of public issuances of unsecured senior notes; and (4) our public issuance of $8,478 outstanding principal amount of convertible senior notes.

Our $1,000,000 unsecured revolving credit facility is available for general business purposes, including acquisitions. The maturity date of our unsecured revolving credit facility is July 15, 2018 and, subject to the payment of an extension fee and meeting other conditions, we have the option to extend the stated maturity date of our unsecured revolving credit facility by one year to July 15, 2019. We can borrow, repay and reborrow funds available under our unsecured revolving credit facility until maturity, and no principal repayment is due until maturity. We are required to pay interest on borrowings under our unsecured revolving credit facility at an annual rate of LIBOR plus a premium, which was 110 basis points as of March 31, 2016. We also pay a facility fee on the total amount of lending commitments, which was 20 basis points per annum at March 31, 2016 under our unsecured revolving credit facility. Both the interest rate premium and the facility fee are subject to adjustment based upon changes to our credit ratings. As of March 31, 2016, the annual interest rate for the amount outstanding under our unsecured revolving credit facility was 1.53%. The weighted average annual interest rate for borrowings under our unsecured revolving credit facility was 1.53% and 1.27% for the three months ended March 31, 2016 and 2015, respectively. As of March 31, 2016 and May 9, 2016, we had $230,000 and $139,000 outstanding under our unsecured revolving credit facility, respectively.

Our $400,000 unsecured term loan, which matures on April 15, 2019, is prepayable without penalty at any time. We are required to pay interest on the amounts under our unsecured term loan at a rate of LIBOR plus a premium, which was 120 basis points as of March 31, 2016. The interest rate premium is subject to adjustment based on changes to our credit ratings. As of March 31, 2016, the annual interest rate for the amount outstanding under our unsecured term loan was 1.64%. The weighted average annual interest rate for borrowings under our unsecured term loan was 1.62% and 1.37% for the three months ended March 31, 2016 and 2015, respectively.

Our credit agreement for our unsecured revolving credit facility and unsecured term loan also includes a feature under which maximum aggregate borrowings may be increased up to $2,300,000 on a combined basis in certain circumstances. Our credit agreement for our unsecured revolving credit facility and unsecured term loan and our unsecured notes indentures and their supplements provide for acceleration of payment of all amounts outstanding upon the occurrence and continuation of certain events of default, such as, in the case of our credit agreement, a change of control of us, which includes The RMR Group LLC, or RMR LLC, ceasing to act as our business manager. Our credit agreement for our unsecured revolving credit facility and unsecured term loan and our senior unsecured notes indentures and their supplements also contain a number of covenants, including covenants that restrict our ability to incur debts or to make distributions under certain circumstances and generally require us to maintain certain financial ratios. We believe we were in compliance with the terms and conditions of our credit agreement for our unsecured revolving credit facility and unsecured term loan and our senior unsecured notes indentures and their supplements at March 31, 2016.

On February 3, 2016, we issued $750,000 aggregate principal amount of unsecured senior notes in public offerings, which included $400,000 aggregate principal amount of 4.25% unsecured senior notes due 2021 and $350,000 aggregate principal amount 5.25% unsecured senior notes due 2026. Net proceeds from these offerings were $731,523 after original issue discounts and offering expenses.

On March 11, 2016, we redeemed at par all of our outstanding 6.30% senior notes due 2016 for $275,000 and unpaid interest (an aggregate of $279,139) using cash on hand and borrowings under our unsecured revolving credit facility. As a result of the redemption, we recorded a loss on early extinguishment of debt of $70 in the three months ended March 31, 2016 which represented the unamortized discounts and issuance costs of these notes.