v2.4.0.6

Other long-term liabilities (Tables)

12 Months Ended

Dec. 31, 2012

Other long-term liabilities

Schedule of other long-term liabilities

		2012			2011
Asset retirement obligations		$	57,816		$	52,336
Net pension liability			4,811			2,243
Deferred revenue			4,919			1,623
Other			3,828			1,657
		$	71,374		$	57,859

Schedule of asset retirement obligations in acquisition of CPILP

The following table represents the fair value of ARO at the date of acquisition along with the additions, reductions and accretion related to our ARO for the year ended December 31, 2012:

		2012
Asset retirement obligations beginning of year		$	52,336
Asset retirement obligation additions			3,466
Accretion of asset retirement obligations			1,590
Translation adjustments			424
Asset retirement obligations, end of year		$	57,816

X

- Definition

Tabular disclosure of other noncurrent liabilities.

+ References

No definition available.

+ Details

Name:	at_ScheduleOfOtherLiabilitiesNoncurrentTableTextBlock
Namespace Prefix:	at_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_OtherLiabilitiesDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859

+ Details

Name:	us-gaap_ScheduleOfChangeInAssetRetirementObligationTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration