XML 181 R51.htm IDEA: XBRL DOCUMENT v3.22.0.1
ASSET RETIREMENT OBLIGATIONS (Tables)
12 Months Ended
Dec. 31, 2021
ASSET RETIREMENT OBLIGATIONS  
Schedule of activity affecting the asset retirement and mine closing liability

Year Ended December 31, 

 

    

2021

    

2020

 

(in thousands)

Beginning balance

$

127,898

$

137,514

Accretion expense

 

3,688

 

4,033

Payments

 

(1,383)

 

(1,769)

Allocation of liability associated with acquisitions, mine development and change in assumptions

 

896

 

(11,880)

Ending balance

$

131,099

$

127,898

Schedule of estimated payments of asset retirement obligations

Year Ended

December 31, 

    

(in thousands)

 

2022

$

7,582

2023

 

2,232

2024

 

558

2025

 

3,788

2026

 

7,256

Thereafter

 

208,021

Aggregate undiscounted asset retirement obligations

 

229,437

Effect of discounting

 

(98,338)

Total asset retirement obligations

 

131,099

Less: current portion

 

(7,582)

Non-current asset retirement obligations

$

123,517