Intangible Assets, Goodwill and Other Assets (Tables)

12 Months Ended

Dec. 31, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets

The following table reflects the components of intangible assets being amortized at December 31, 2017 and 2016:

		December 31, 2017						December 31, 2016
	Weighted Amortization Period in Years	Gross Carrying Amount		Accumulated Amortization		Carrying Value		Gross Carrying Amount		Accumulated Amortization		Carrying Value
Sodium Minerals and Sulfur Services:
Customer relationships	5	$	94,654	$	92,493	$	2,161	$	94,654	$	89,756	$	4,898
Licensing agreements	6	38,678		36,528		2,150		38,678		34,204		4,474
Non-compete agreement	3	800		89		711		—		—		—
Segment total		134,132		129,110		5,022		133,332		123,960		9,372
Onshore Facilities & Transportation:
Customer relationships	5	35,430		35,082		348		35,430		33,676		1,754
Intangibles associated with lease	15	13,260		4,933		8,327		13,260		4,459		8,801
Segment total		48,690		40,015		8,675		48,690		38,135		10,555
Marine contract intangible	5	27,000		11,700		15,300		27,000		6,300		20,700
Offshore pipeline contract intangibles	19	158,101		20,109		137,992		158,101		11,788		146,313
Other	5	28,900		13,483		15,417		28,569		10,622		17,947
Total		$	396,823	$	214,417	$	182,406	$	395,692	$	190,805	$	204,887

Schedule of Estimated Amortization Expense

The following table reflects our estimated amortization expense for each of the five subsequent fiscal years:

	2018		2019		2020		2021		2022
Sodium Minerals and Sulfur Services:
Customer relationships	$	2,161	$	—	$	—	$	—	$	—
Licensing agreements	2,150		—		—		—		—
Non Compete	267		267		177		—		—
Onshore Facilities & Transportation:
Customer relationships	41		39		38		37		35
Intangibles associated with lease	474		474		474		474		474
Marine contract intangibles	5,400		5,400		4,500		—		—
Offshore pipeline contract intangibles	8,321		8,321		8,321		8,321		8,321
Other	2,974		2,952		2,921		1,810		1,652
Total	$	21,788	$	17,453	$	16,431	$	10,642	$	10,482

Schedule of Other Assets

Other assets consisted of the following:

	December 31,
	2017		2016
CO2 volumetric production payments, net of amortization	$	2,175	$	3,503
Deferred marine charges, net (1)	30,246		27,710
Other deferred costs and deposits	24,207		25,398
Other assets, net of amortization	$	56,628	$	56,611

(1) See discussion of deferred charges on marine transportation assets in the Summary of Accounting Policies (Note 2)