Note 15 - Asset Retirement Obligation

12 Months Ended

Dec. 31, 2016

Notes to Financial Statements

Asset Retirement Obligation Disclosure [Text Block]

NOTE

15

 — ASSET RETIREMENT OBLIGATION

The following table presents a reconciliation of the beginning and ending aggregate carrying amount of asset retirement obligation for the years presented below:

	Year Ended December 31,
	2016		2015
	(Dollars in thousands)
Balance at beginning of year	$	20,856	$	19,142
Revision in estimated cash flows		303		(681	)
Liabilities incurred		540		859
Accretion expense		1,649		1,536
Balance at end of year	$	23,348	$	20,856