XML 27 R17.htm IDEA: XBRL DOCUMENT v3.7.0.1
Asset Retirement Obligation (Notes)
 6 Months Ended
Jun. 30, 2017
Asset Retirement Obligation [Abstract]  
Asset Retirement Obligation Disclosure [Text Block]
Asset Retirement Obligation
The Company's asset retirement obligations represent the estimated cost of decommissioning the turbines, removing above-ground installations and restoring the sites at the end of its estimated economic useful life.
The following table presents a reconciliation of the beginning and ending aggregate carrying amounts of asset retirement obligation (in thousands):
 
 
Six months ended June 30,
 
 
2017
 
2016
Beginning asset retirement obligations
 
$
44,783

 
$
42,197

Net additions during the period (1)
 
5,994

 
—

Foreign currency translation adjustment
 
91

 
159

Accretion expense
 
1,357

 
1,260

Ending asset retirement obligations
 
$
52,225

 
$
43,616