v2.4.0.8

Stock Option and Incentive Plan (Restricted Stock) (Narrative) (Details) (USD $) | 3 Months Ended | 6 Months Ended |  | 6 Months Ended | 0 Months Ended |  | 6 Months Ended
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Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012 | Dec. 31, 2012 | Jun. 30, 2013 Restricted Stock [Member] | Jun. 30, 2013 LTIP Units [Member] | Jan. 28, 2013 MYLTIP [Member] Y | Jun. 30, 2013 MYLTIP [Member] | Jun. 30, 2013 LTIPs And Restricted Stock [Member] VestingInstallments | Jun. 30, 2013 LTIPs and OPP Awards [Member] | Jun. 30, 2013 Non Qualified Stock Options [Member] | Jun. 30, 2013 Unvested 2011 and 2012 OPP Units and 2013 MYLTIPS [Member] | Jun. 30, 2013 Board of Directors Chairman [Member] | Jun. 30, 2012 Executive Vice President [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued | 152,463,640 |  | 152,463,640 |  | 151,680,119 | 36,730 |  |  |  |  |  |  |  |  |
LTIP units issued (in shares) |  |  |  |  |  |  | 184,733 |  |  |  |  |  |  |  |
MYLTIP units issued (in shares) |  |  |  |  |  |  |  |  | 318,926 |  |  |  |  |  |
Non-qualified stock options issued |  |  |  |  |  |  |  |  |  |  |  | 252,220 |  |  |
Employee and director payment per share (in dollars per share) |  |  |  |  |  | $ 0.01 |  |  |  |  | $ 0.25 |  |  |  |
Vesting annual installments |  |  |  |  |  |  |  |  |  | 4 |  |  |  |  |
Stock-based compensation associated with restricted stock, non-qualified options, LTIP Units, 2008 OPP Units, 2011 OPP Units, and 2012 OPP Units and 2013 MYLTIPS | $ 6,400,000 | $ 6,400,000 | $ 31,900,000 | $ 17,400,000 |  |  |  |  |  |  |  |  |  |  | $ 2,700,000
Acceleration of Stock Basec Compensation and Stock Based Compensation Associated with Transition Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  | 18,600,000 |
TRS Measurement, Years |  |  |  |  |  |  |  | 3 |  |  |  |  |  |  |
Unrecognized compensation expenses |  |  |  |  |  |  |  |  |  | 22,900,000 |  |  | 14,300,000 |  |
Weighted-average period (years) |  |  |  |  |  |  |  |  |  |  |  |  | 3 years 0 months 0 days |  |
Value of shares of common stock | 1,524,000 |  | 1,524,000 |  | 1,516,000 | 3,900,000 |  |  |  |  |  |  |  |  |
Employee's weighted average cost per share (in dollars per share) |  |  |  |  |  | $ 105.30 |  |  |  |  |  |  |  |  |
Value of LTIP units issued |  |  |  |  |  |  | $ 14,800,000 |  |  |  |  |  |  |  |
Per unit fair value weighted-average (in dollars per share) |  |  |  |  |  |  | $ 96.33 |  |  |  |  |  |  |  |
Expected life assumed to calculate per unit fair value per LTIP unit (years) |  |  |  |  |  |  | 5 years 8 months 12 days |  |  |  |  | 6 years 0 months 0 days |  |  |
Risk-free rate |  |  |  |  |  |  | 1.03% |  |  |  |  | 1.11% |  |  |
Expected price volatility |  |  |  |  |  |  | 26.00% |  |  |  |  | 26.00% |  |  |
Expected dividend rate |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |
Method of valuation |  |  |  |  |  |  | Monte Carlo simulation method |  |  |  |  | The non-qualified stock options granted during the nine months ended March 31, 2013 had a weighted-average fair value on the date of grant of $18.64 per option, which was computed using the Black-Scholes option-pricing model utilizing the following weighted-average assumptions: an expected life of 6.3 years, a risk-free interest rate of 1.19%, an expected price volatility of 26% and an expected dividend yield of 3%. |  |  |
Weighted-average grant date fair value (in dollars per share) |  |  |  |  |  |  |  |  |  |  |  | $ 18.46 |  |  |
Weighted-average exercise price (in dollars per share) |  |  |  |  |  |  |  |  |  |  |  | $ 105.10 |  |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
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- Definition Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section D -Subsection 2 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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