Asset Retirement Obligations and Other Liabilities (Tables)
 12 Months Ended
Dec. 31, 2015
Asset Retirement Obligation Disclosure [Abstract]  
Activity in Asset Retirement Obligations
Activity in asset retirement obligations for the years ended December 31, 2015 and 2014 is as follows:
 
 
Year Ended December 31,
(In thousands)
 
2015
 
2014
Balance at the beginning of the year
 
$
5,049

 
$
2,553

     Additional obligations
 
863

 
2,930

Assumed through acquisition
 
3,690

 
—

     Accretion expense
 
369

 
243

Foreign currency translation adjustment
 
(1,342
)
 
(677
)
Balance at the end of the year
 
$
8,629

 
$
5,049