Debt Carrying Value of Debt Instruments (Tables) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jul. 14, 2016
Debt Instrument [Line Items]
Debt Instrument, Principal Value	$ 286,600	$ 288,732
Bank loan	4,417	4,917
Notes Payable	201,543	203,648
Debt Instrument, Unamortized Discount (Premium), Net	258,782	260,670
Total liabilities	237,792	244,141
Long-term Debt, Fair Value	180,807	187,172
Subordinated debt, at fair value	52,822	52,105
Long-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Principal Value	191,683	193,315
Total liabilities	52,822	52,105
Long-term Debt, Fair Value			$ 191,700
Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Principal Value	90,500	90,500
Debt Instrument, Unamortized Discount (Premium), Net	52,822	52,105
Operating Segments [Member]
Debt Instrument [Line Items]
Notes Payable	184,567	186,469
Long-term Debt, Fair Value	163,059	168,477
Operating Segments [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Principal Value	174,707	176,136
Other Segments [Member]
Debt Instrument [Line Items]
Notes Payable	7,976	8,179
Long-term Debt, Fair Value	8,003	8,825
Other Segments [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Principal Value	7,976	8,179
Consolidated Entities [Member]
Debt Instrument [Line Items]
Notes Payable	9,000	9,000
Long-term Debt, Fair Value	9,745	9,870
Consolidated Entities [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Principal Value	$ 9,000	$ 9,000

Debt Instrument, Principal Value

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- Definition

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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Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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