Realized and Unrealized Gains and Losses on Assets and Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Fair Value Assets And Liabilities Measured On Unobservable Inputs [Line Items]
Change in fair value of financial instruments, Liabilities	$ (1,941)		$ (3,010)
Change in fair value of financial instruments	111	$ 3,093	198	$ 1,940
Junior subordinated notes
Fair Value Assets And Liabilities Measured On Unobservable Inputs [Line Items]
Change in fair value of financial instruments, Liabilities	(77)	(42)	(272)	(702)
Derivative
Fair Value Assets And Liabilities Measured On Unobservable Inputs [Line Items]
Change in fair value of financial instruments, Liabilities	$ 188	(265)	$ 470	(258)
Fair Value, Measurements, Recurring \| Warrants and investor SARs
Fair Value Assets And Liabilities Measured On Unobservable Inputs [Line Items]
Change in fair value of financial instruments, Liabilities		$ 3,400		$ 2,900

Fair value assets and liabilities measured on unobservable inputs.

No definition available.

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- Definition

Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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