Fair Value - Presentation of Carrying Values and Fair Values of Certain Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Assets:
Investments, available-for-sale	$ 117,212	$ 131,582
Other investments	9,994	11,256
Liabilities:
Debentures payable	40,302	40,256
Term loan from principal stockholder	29,779	29,753
Carrying Value
Assets:
Investments, available-for-sale	117,212	131,582
Other investments	9,994	11,256
Liabilities:
Debentures payable	40,302	40,256
Term loan from principal stockholder	29,779	29,753
Fair Value
Assets:
Investments, available-for-sale	117,212	131,582
Other investments	9,994	11,256
Liabilities:
Debentures payable	11,488	20,275
Term loan from principal stockholder	$ 15,000	$ 28,504

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of investments classified as other.

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