Accounting for Suspended Exploratory Wells (Tables)

12 Months Ended

Dec. 31, 2015

Accounting for Suspended Exploratory Wells [Abstract]

Changes in company's suspended exploratory well costs

The following table indicates the changes to the company’s suspended exploratory well costs for the three years ended December 31, 2015:

	2015			2014			2013
Beginning balance at January 1	$	4,195		$	3,245		$	2,681
Additions to capitalized exploratory well costs pending the determination of proved reserves	869			1,591			885
Reclassifications to wells, facilities and equipment based on the determination of proved reserves	(164		)	(298		)	(290		)
Capitalized exploratory well costs charged to expense	(1,397		)	(312		)	(31		)
Other reductions*	(191		)	(31		)	—
Ending balance at December 31	$	3,312		$	4,195		$	3,245

^*    Represents property sales.

Aging of capitalized well costs and number of project

The following table provides an aging of capitalized well costs and the number of projects for which exploratory well costs have been capitalized for a period greater than one year since the completion of drilling.

	At December 31
	2015		2014		2013
Exploratory well costs capitalized for a period of one year or less	$	489	$	1,522	$	641
Exploratory well costs capitalized for a period greater than one year	2,823		2,673		2,604
Balance at December 31	$	3,312	$	4,195	$	3,245
Number of projects with exploratory well costs that have been capitalized for a period greater than one year*	39		51		51

^*    Certain projects have multiple wells or fields or both.

Aging of Costs on Well and Project Basis

The tables below contain the aging of these costs on a well and project basis:

Aging based on drilling completion date of individual wells:	Amount		Number of wells
1998-2004	$	285	26
2005-2009	395		33
2010-2014	2,143		106
Total	$	2,823	165
Aging based on drilling completion date of last suspended well in project:	Amount		Number of projects
2003-2007	$	200	4
2008-2011	393		6
2012-2015	2,230		29
Total	$	2,823	39