Investments - Cost or Amortized Cost and Fair Value of Securities Available for Sale (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	$ 388,389	$ 355,052
Gross Unrealized Gains	493	3,541
Gross Unrealized Losses	(3,012)	(4,153)
Fair Value	385,870	354,440
U.S. Government Obligations and Agencies [Member] \| Fixed Maturities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	116,903	105,229
Gross Unrealized Gains	64	19
Gross Unrealized Losses	(884)	(1,033)
Fair Value	116,083	104,215
Corporate Bonds [Member] \| Fixed Maturities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	109,946	94,708
Gross Unrealized Gains	216	265
Gross Unrealized Losses	(325)	(770)
Fair Value	109,837	94,203
Mortgage-Backed and Asset-Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	95,599	91,502
Fair Value	95,238	91,000
Mortgage-Backed and Asset-Backed Securities [Member] \| Fixed Maturities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	95,599	91,502
Gross Unrealized Gains	141	75
Gross Unrealized Losses	(502)	(577)
Fair Value	95,238	91,000
Redeemable Preferred Stock [Member] \| Fixed Maturities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	6,813
Gross Unrealized Gains	71
Gross Unrealized Losses	(32)
Fair Value	6,852
Common Stock [Member] \| Equity Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	331	8,500
Gross Unrealized Gains	1	916
Gross Unrealized Losses	(82)	(121)
Fair Value	250	9,295
Mutual Funds [Member] \| Equity Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	21,297	55,113
Gross Unrealized Gains		2,266
Gross Unrealized Losses	(1,160)	(1,652)
Fair Value	20,137	55,727
Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Cost or Amortized Cost	37,500
Gross Unrealized Gains	0
Gross Unrealized Losses	(27)
Fair Value	$ 37,473

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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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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