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Share and Unit-Based Plans - Narrative (Details) $ / shares in Units, $ in Thousands |  |  | 3 Months Ended
--- | --- | --- | ---
Mar. 04, 2016 $ / shares shares | Jan. 01, 2016 $ / shares shares | Mar. 31, 2016 USD ($) $ / shares shares | Mar. 31, 2015 USD ($)
Share and unit-based plans |  |  |  |
Capitalized share and unit-based compensation costs | $ |  |  | $ 4,959 | $ 4,347
Stock units |  |  |  |
Share and unit-based plans |  |  |  |
Conversion rate of shares |  |  | 1 |
Granted (in shares) | shares |  |  | 85,045 |
Average grant date fair value (in dollars per share) | $ / shares |  |  | $ 79.24 |
Unrecognized compensation cost of share and unit-based plans | $ |  |  | $ 6,628 |
LTIP Units |  |  |  |
Share and unit-based plans |  |  |  |
Conversion rate of shares |  |  | 1 |
Granted (in shares) | shares |  |  | 480,371 |
Average grant date fair value (in dollars per share) | $ / shares |  |  | $ 65.00 |
Risk free rate (as a percent) |  | 1.32% |  |
Volatility (as a percent) |  | 20.31% |  |
Unrecognized compensation cost of share and unit-based plans | $ |  |  | $ 17,955 |
Stock options |  |  |  |
Share and unit-based plans |  |  |  |
Unrecognized compensation cost of share and unit-based plans | $ |  |  | $ 23 |
Phantom stock units |  |  |  |
Share and unit-based plans |  |  |  |
Granted (in shares) | shares |  |  | 14,534 |
Average grant date fair value (in dollars per share) | $ / shares |  |  | $ 80.42 |
Unrecognized compensation cost of share and unit-based plans | $ |  |  | $ 746 |
LTIP units that vest in equal installments over a service period ending December 31, 2016 | LTIP Units |  |  |  |
Share and unit-based plans |  |  |  |
Granted (in shares) | shares |  | 58,786 |  |
Average grant date fair value (in dollars per share) | $ / shares |  | $ 80.69 |  |
Market-Indexed LTIP units that vest in equal installments over a service period ending December 31, 2016 | LTIP Units |  |  |  |
Share and unit-based plans |  |  |  |
Granted (in shares) | shares |  | 266,899 |  |
Average grant date fair value (in dollars per share) | $ / shares |  | $ 53.32 |  |
LTIP units that are fully vested on the grant date | LTIP Units |  |  |  |
Share and unit-based plans |  |  |  |
Granted (in shares) | shares | 154,686 |  |  |
Average grant date fair value (in dollars per share) | $ / shares | $ 79.20 |  |  |

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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments, Other than Options, Conversion Rate + References No definition available. + Details
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- Definition Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, 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 2 -Subparagraph (h)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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 The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + 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 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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