Subsequent Events	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	9. Subsequent Events On October 19, 2021 (the "Closing Date") we acquired 100% of the equity interest of Choptank Transport, LLC ("Choptank") for approximately $130 million in cash. In connection with the acquisition, we granted approximately $20 million of restricted stock to Choptank's owners and senior management team, which is subject to certain vesting conditions. The grants of restricted stock were made pursuant to award agreements and issued under our 2002 Long Term Incentive Plan. The acquisition enhances our over-the-road refrigerated transportation solutions offering and complements our growing fleet of refrigerated intermodal containers. Choptank has developed a best-in-class proprietary technology platform that we will leverage to enhance our truck brokerage service line. We incurred approximately $1.1 million of costs associated with this transaction prior to the Closing Date that are reflected in General and administrative expenses in the Unaudited Consolidated Statements of Income and Comprehensive Income for the three and nine months ended September 30, 2021.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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