Share and Unit-Based Plans: Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share and unit-based plans
Compensation cost under share and unit-based plans	$ 34,873	$ 28,122	$ 14,970
Additional compensation cost from modified terms of awards due to employee separations			1,214
Capitalized share and unit-based compensation costs	5,410	3,915	2,646
Stock awards
Share and unit-based plans
Compensation cost under share and unit-based plans	365	497	598
Unrecognized compensation cost of share and unit-based plans	248
Stock units
Share and unit-based plans
Compensation cost under share and unit-based plans	4,689	3,839	3,379
Unrecognized compensation cost of share and unit-based plans	2,843
LTIP units
Share and unit-based plans
Compensation cost under share and unit-based plans	28,598	22,778	9,436
Number of awards with modified terms due to separation agreement			20,000
Unrecognized compensation cost of share and unit-based plans	2,751
SARs
Share and unit-based plans
Compensation cost under share and unit-based plans	0	0	583
Number of awards with modified terms due to separation agreement			54,405
Stock awards and units
Share and unit-based plans
Fair value of equity-based awards vested during period	4,685	3,516	30,454
Stock options
Share and unit-based plans
Compensation cost under share and unit-based plans	16	16	21
Unrecognized compensation cost of share and unit-based plans	43
Phantom stock units
Share and unit-based plans
Compensation cost under share and unit-based plans	1,205	992	953
Unrecognized compensation cost of share and unit-based plans	$ 541

Represents the number of share-based payment instruments affected by a modification to the award plan.

No definition available.

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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.

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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.

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Unrecognized cost of unvested share-based compensation awards.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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