Cash and Cash Equivalents	9 Months Ended
Sep. 30, 2017
Cash and Cash Equivalents [Abstract]
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents are short-term, highly liquid investments with insignificant interest rate risk and original maturities of three months or less at acquisition. At September 30, 2017, restricted and designated cash and investments totaled $32.5 million, of which $11.6 million was included in other current assets ($5.5 million related to designated funds for equipment purchases and $6.1 million related to designated funds for claims acquired from the acquisition of IDC) and $20.9 million was included in other non-current assets in the consolidated balance sheet. Restricted and designated cash and investments totaled $21.7 million at December 31, 2016, of which $9.3 million was included in other current assets and $12.4 million was included in other non-current assets in the consolidated balance sheet. The restricted funds represent deposits required by state agencies for self-insurance purposes and designated funds that are earmarked for a specific purpose and not for general business use.

The entire disclosure for cash and cash equivalent footnotes, which may include the types of deposits and money market instruments, applicable carrying amounts, restricted amounts and compensating balance arrangements. Cash and equivalents include: (1) currency on hand (2) demand deposits with banks or financial institutions (3) other kinds of accounts that have the general characteristics of demand deposits (4) short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments maturing within three months from the date of acquisition qualify.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 305
-URI http://asc.fasb.org/topic&trid=2122426

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