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Share and Unit-Based Plans - Narrative (Details) $ / shares in Units, $ in Thousands |  |  |  |  | 3 Months Ended | 6 Months Ended
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Jun. 01, 2017 $ / shares shares | May 30, 2017 $ / shares shares | Mar. 03, 2017 $ / shares shares | Jan. 01, 2017 $ / shares shares | Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) $ / shares shares | Jun. 30, 2016 USD ($)
Share and unit-based plans |  |  |  |  |  |  |  |
Capitalized share and unit-based compensation costs | $ |  |  |  |  | $ 926 | $ 781 | $ 4,295 | $ 5,740
Stock units |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Conversion rate of shares |  |  |  |  |  |  | 1 |
Granted (in shares) | shares |  |  |  |  |  |  | 85,979 |
Average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 66.53 |
Unrecognized compensation cost of share and unit-based plans | $ |  |  |  |  | 5,545 |  | $ 5,545 |
LTIP Units |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Conversion rate of shares |  |  |  |  |  |  | 1 |
Granted (in shares) | shares |  |  |  |  |  |  | 506,906 |
Average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 55.33 |
Risk free rate | 1.45% |  |  | 1.49% |  |  |  |
Volatility | 21.40% |  |  | 20.75% |  |  |  |
Unrecognized compensation cost of share and unit-based plans | $ |  |  |  |  | 10,823 |  | $ 10,823 |
LTIP Units | LTIP units that vest in equal installments over a service period ending December 31, 2016 |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Granted (in shares) | shares | 1,522 |  |  | 66,079 |  |  |  |
Average grant date fair value (in dollars per share) | $ 58.31 |  |  | $ 70.84 |  |  |  |
LTIP Units | Market-Indexed LTIP units that vest in equal installments over a service period ending December 31, 2016 |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Granted (in shares) | shares | 6,714 |  |  | 297,849 |  |  |  |
Average grant date fair value (in dollars per share) | $ 39.66 |  |  | $ 47.15 |  |  |  |
LTIP Units | LTIP units that are fully vested on the grant date |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Granted (in shares) | shares |  |  | 134,742 |  |  |  |  |
Average grant date fair value (in dollars per share) |  |  | $ 66.57 |  |  |  |  |
Non-qualified stock options |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Granted (in shares) | shares |  | 25,000 |  |  |  |  |  |
Average grant date fair value (in dollars per share) |  | $ 10.02 |  |  |  |  |  |
Risk free rate |  | 2.08% |  |  |  |  |  |
Volatility |  | 30.19% |  |  |  |  |  |
Dividend yield |  | 4.93% |  |  |  |  |  |
Current value (in dollars per share) |  | $ 57.55 |  |  |  |  |  |
Expected term |  | 8 years |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Unrecognized compensation cost of share and unit-based plans | $ |  |  |  |  | 242 |  | $ 242 |
Phantom stock units |  |  |  |  |  |  |  |
Share and unit-based plans |  |  |  |  |  |  |  |
Granted (in shares) | shares |  |  |  |  |  |  | 6,772 |
Average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 71.73 |
Unrecognized compensation cost of share and unit-based plans | $ |  |  |  |  | $ 560 |  | $ 560 |

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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=96867065&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=96867065&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=96867065&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=96867065&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=96867065&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=96867065&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=96867065&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 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 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.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 + Details
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