Property And Equipment

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment [Abstract]

Property and Equipment

The following is a summary of the gross components of property and equipment (dollars in thousands):



		December 31,
	Estimated Useful Life	2017		2016

Vessels	15 to 30 years	$	2,083,267	$	1,860,379
ROVs, trenchers and ROVDrills	10 years	298,227		309,603
Machinery, equipment and leasehold improvements	5 to 15 years	314,278		280,908
Total property and equipment		$	2,695,772	$	2,450,890

Our assessment at December 31, 2015 indicated impairment on the Helix 534 and the HP I. We impaired these assets based on the difference between the carrying amount and the estimated fair value. We recorded an impairment charge of $205.2 million to reduce the carrying amount of the Helix 534 to its estimated fair value of $1.0 million and to write off associated deferred dry dock costs of $9.0 million. The fair value of the Helix 534 was based on its estimated salvage value according to current market pricing. We recorded an impairment charge of $133.4 million to reduce the carrying amount of the HP I to its estimated fair value of $124.3 million. We estimated the fair value of the HP I based on the present value of its expected future cash flows. In addition, we recorded impairment charges of $6.3 million to write off capitalized costs associated with certain vessel projects that we no longer expected to materialize.

In January 2016, we sold our office and warehouse property located in Aberdeen, Scotland for approximately $11 million and entered into a separate agreement with the same party to lease back the facility for a lease term of 15 years with two five-year options to extend the lease at our option. A gain of approximately $7.6 million from the sale of this property is deferred and amortized over the 15-year minimum lease term.

In December 2016, we sold the Helix 534 vessel to a third party for approximately $2.8 million, including $0.4 million held in escrow which was not subsequently realized. We recorded a gain of approximately $1.3 million from the sale, net of selling expenses.