v3.19.3.a.u2

Other long-term liabilities (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018
Long-term contract liability |  | $ 0.2 |
Net pension liability |  | 1.2 | $ 1.2
Accrued LTIP and director share units |  | 1.6 | 1.4
Other |  | 1.7 | 2.4
Other long-term liabilities |  | 4.7 | 5.0
Asset retirement obligations rollforward |  |  |
Asset retirement obligations beginning of year |  | 49.2 | 45.3
Accretion and change in estimate of asset retirement obligation |  | 2.3 | 4.3
Acquisition |  |  | 1.8
Costs incurred |  | (1.0) | (0.5)
Translation adjustments |  | 1.0 | (1.7)
Asset retirement obligations, end of year | $ 45.3 | 51.5 | 49.2
San Diego Projects |  |  |
Asset retirement obligations rollforward |  |  |
Acquisition | 6.7 |  |
Amortization expense of intangible assets | 5.0 |  |
Amount of increase in asset retirement obligations |  | $ 1.4 | $ 3.5
Asset Impairment Charges |  |  |
Project removal obligation | $ 1.7 |  |

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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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