Dispositions and acquisitions	3 Months Ended
Mar. 31, 2020
Business Combinations [Abstract]
Dispositions and acquisitions	(9) Dispositions and acquisitions Three-month period ended March 31, 2020: Acquisitions: During the first three months of 2020, there were no acquisitions. Divestitures: During the first three months of 2020, there were no divestitures. Three-month period ended March 31, 2019: Acquisitions: During the first three months of 2019, there were no acquisitions. Divestitures: During the first three months of 2019, there were no divestitures.

The entire disclosure for business combinations, including leverage buyout transactions (as applicable), and divestitures. This may include a description of a business combination or divestiture (or series of individually immaterial business combinations or divestitures) completed during the period, including background, timing, and assets and liabilities recognized and reclassified or sold. This element does not include fixed asset sales and plant closings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-URI http://asc.fasb.org/subtopic&trid=2122178

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-URI http://asc.fasb.org/topic&trid=2303972

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