Asset Retirement Obligations (Notes)

12 Months Ended

Dec. 31, 2014

Asset Retirement Obligation Disclosure [Abstract]

ASSET RETIREMENT OBLIGATIONS

These accrued obligations relate to underground storage caverns, offshore platforms, pipelines, and gas transmission facilities. At the end of the useful life of each respective asset, we are legally obligated to plug storage caverns and remove any related surface equipment, to dismantle offshore platforms, to cap certain gathering pipelines at the wellhead connection and remove any related surface equipment, and to remove certain components of gas transmission facilities from the ground.

During 2014 and 2013, our overall asset retirement obligation changed as follows (in thousands):



	2014			2013
Beginning balance	$	273,987		$	296,870
Accretion	17,962			31,461
New obligations	1,346			2,225
Changes in estimates of existing obligations (1)	23,031			(27,628		)
Property dispositions/obligations settled	(19,851		)	(28,941		)
Ending balance	$	296,475		$	273,987

(1)

Changes in estimates of existing obligations are primarily due to the annual review process, which considers various factors including inflation rates, current estimates for removal cost, discount rates, and the estimated remaining life of assets. The 2014 changes in estimates of existing obligations reflect an increase of $23 million due to revisions in the estimated remaining life of assets, inflation rates, discount rates, and current estimates for removal costs. The 2013 changes in estimates of existing obligations reflect a decrease of $28 million, primarily due to a decrease of $36 million due to revisions in the estimated remaining life of assets, inflation rates, discount rates, and current estimates for removal costs, partially offset by an increase of $9 million related to changes in timing and method of abandonment of our Eminence natural gas storage caverns that were associated with a leak in 2010.

We are entitled to collect in rates the amounts necessary to fund our ARO. All funds received for such retirements are deposited into an external trust account dedicated to funding our ARO. Under our current rate settlement our annual funding obligation is approximately $36.4 million, with installments to be deposited monthly.