Long-Term Debt Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term Debt, Fair Value	$ 164,270	$ 164,651
150M Senior Notes
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Dec. 15, 2027
Debt Instrument, Interest Rate, Effective Percentage	6.25%
Long-term Debt, Fair Value	$ 150,000	150,000
BB&T Term Note Payable
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	May 26, 2031
Debt Instrument, Interest Rate, Effective Percentage	3.31%
Long-term Debt, Fair Value	$ 4,564	4,651
Florida State Board of Administration
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jul. 01, 2026
Debt Instrument, Interest Rate, Effective Percentage	2.43%
Long-term Debt, Fair Value	$ 9,706	$ 10,000

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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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.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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