Goodwill and Other Intangibles (Changes in Net Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill and Other Intangibles
Goodwill, beginning balance	$ 807,260	$ 789,058
Change in goodwill related to small acquisitions	1,464	18,202
Provisional goodwill and intangibles related to Mayasa acquisition	128,090	0
Goodwill, ending balance	936,814	$ 807,260
Mayasa
Goodwill and Other Intangibles
Provisional goodwill and intangibles related to Mayasa acquisition	$ 128,100

The carrying amount as on the balance sheet date of goodwill and intangibles acquired in business combination.

No definition available.

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- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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