Debt (Details 1) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Line of Credit	$ 0	$ 0
Other indebtedness	83,000	96,000
Total Debt	512,829,000	477,137,000
Less: current portion	(82,179,000)	(6,360,000)
Total Long-Term Debt	430,650,000	470,777,000
5.75% Unsecured Notes due June 1, 2026 [Member]
Debt Instrument [Line Items]
Unsecured notes	395,393,000	394,675,000
Unamortized debt issuance costs	4,600,000	5,300,000
Kaplan Four Year Credit Agreement Dated July 14, 2016 [Member]
Debt Instrument [Line Items]
Line of Credit	78,650,000	82,366,000
Unamortized debt issuance costs	100,000	200,000
Commercial note with SunTrust [Member]
Debt Instrument [Line Items]
Notes Payable to Bank	27,500,000	0
Pinnacle Bank Term Loan [Member]
Debt Instrument [Line Items]
Loans Payable to Bank	$ 11,203,000	$ 0

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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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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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the normal operating cycle if longer.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Including the current and noncurrent portions, the carrying value as of the balance sheet date of notes payable to banks, excluding mortgage notes, initially due beyond one year or beyond the operating cycle if longer.

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Amount of long-term debt classified as other.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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