v2.4.0.8

Unsecured Exchangeable Senior Notes Schedule of Unsecured Exchangeable Senior Notes (Details) (USD $) |  |  |  | 6 Months Ended
--- | --- | --- | --- | ---
Jun. 30, 2013 | Dec. 31, 2012 | Aug. 15, 2008 | Jun. 30, 2013 3.625% exchangeable senior notes [Member]
Debt Instrument [Line Items] |  |  |  |  |
Coupon/Stated Rate |  |  |  | 3.625% |
Effective Percentage |  |  |  | 4.037% | [1]
Exchange Rrate |  |  |  | 8.5051 | [2]
Principal Amount |  |  |  | $ 747,500,000 |
Maturity date |  |  |  | Feb. 15, 2014 |
Unsecured exchangeable senior notes, discount | (924,000) | (1,653,000) |  |  |
Adjustment for the equity component allocation, net of accumulated amortization | (12,298,000) |  |  |  |
Unsecured exchangeable senior notes | 734,278,000 | 1,170,356,000 |  |  |
Increment Of The Notes For Purposes Of Disclosing Initial Exchange Rate | 1,000 |  |  |  |
Initial Exchange Rate | 8.5051 |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ 117.58 |  |  |  |
Adjusted Exchange Price Due To Capped Call | $ 137.17 |  |  |  |
Premium Over Closing Price Due To Capped Call | 40.00% |  |  |  |
Share Price | $ 134.38 |  | $ 97.98 |  |
Net Cost Of Capped Call Transaction | $ 44,400,000 |  |  |  |
[1] | Yield on issuance date including the effects of discounts on the notes and the amortization of financing costs but excluding the effects of the adjustment for the equity component allocation.
[2] | The initial exchange rate is 8.5051 shares per $1,000 principal amount of the notes (or an initial exchange price of approximately $117.58 per share of Boston Properties, Inc.’s common stock). In addition, the Company entered into capped call transactions with affiliates of certain of the initial purchasers, which are intended to reduce the potential dilution upon future exchange of the notes. The capped call transactions were intended to increase the effective exchange price to the Company of the notes from $117.58 to approximately $137.17 per share (subject to adjustment), representing an overall effective premium of approximately 40% over the closing price on August 13, 2008 of $97.98 per share of Boston Properties, Inc.’s common stock. The net cost of the capped call transactions was approximately $44.4 million. As of June 30, 2013, the effective exchange price was $134.38 per share.

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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16(a)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 + Details
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- Definition Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 + Details
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