Fair Values of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Summary of Carrying or Reported Values and Corresponding Fair Values for Financial Instruments

The following table summarizes the carrying or reported values and corresponding fair values for financial instruments:

	December 31,
	2017				2016
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(in thousands)
Assets:
Fixed maturity securities—held to maturity	$	629,668	$	639,309	$	562,434	$	568,931
Fixed maturity securities—available for sale		465,594		465,594		479,097		479,097
Equity securities		9,282		9,282		33		33
Short-term investments		25,770		25,770		29,580		29,580
Other investments		—		—		13,330		13,330
Cash and cash equivalents		55,559		55,559		58,936		58,936

Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring basis as of December 31, 2017 and 2016 are as follows:

	December 31, 2017
	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
	(in thousands)
Financial instruments carried at fair value,    classified as part of:
Securities available for sale—fixed maturity:
States and political subdivisions	$	—	$	251,140	$	—	$	251,140
Corporate bonds		—		130,222		—		130,222
U.S. agency-based mortgage-backed securities		—		18,014		—		18,014
U.S. Treasury securities and obligations    of U.S. government agencies		66,218		—		—		66,218
Total available for sale—fixed maturity		66,218		399,376		—		465,594
Securities available for sale—equity:
Domestic common stock		9,248		—		34		9,282
Total available for sale	$	75,466	$	399,376	$	34	$	474,876

	December 31, 2016
	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
	(in thousands)
Financial instruments carried at fair value,    classified as part of:
Securities available for sale—fixed maturity:
States and political subdivisions	$	—	$	232,293	$	—	$	232,293
Corporate bonds		—		182,515		—		182,515
U.S. agency-based mortgage-backed securities		—		9,342		—		9,342
U.S. Treasury securities and obligations    of U.S. government agencies		54,947		—		—		54,947
Total available for sale—fixed maturity		54,947		424,150		—		479,097
Securities available for sale—equity:
Domestic common stock		33		—		—		33
Total available for sale	$	54,980	$	424,150	$	—	$	479,130

Schedule of Assets and Liabilities Measured at Amortized Cost

Assets and liabilities measured at amortized cost as of December 31, 2017 and 2016 are as follows:

	December 31, 2017
	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
	(in thousands)
Securities held-to-maturity—fixed maturity:
States and political subdivisions	$	—	$	469,101	$	—	$	469,101
Corporate bonds		—		100,047		—		100,047
Commercial mortgage-backed securities		—		—		—		—
U.S. agency-based mortgage-backed securities		—		10,845		—		10,845
U.S. Treasury securities		6,750		—		—		6,750
Obligations of U.S. government agencies		—		51,257		—		51,257
Asset-backed securities		—		1,309		—		1,309
Total held-to-maturity	$	6,750	$	632,559	$	—	$	639,309

	December 31, 2016
	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
	(in thousands)
Securities held-to-maturity—fixed maturity:
States and political subdivisions	$	—	$	399,483	$	—	$	399,483
Corporate bonds		—		144,016		—		144,016
Commercial mortgage-backed securities		—		70		—		70
U.S. agency-based mortgage-backed securities		—		10,915		—		10,915
U.S. Treasury securities		6,779		—		—		6,779
Obligations of U.S. government agencies		—		5,637		—		5,637
Asset-backed securities		—		2,031		—		2,031
Total held-to-maturity	$	6,779	$	562,152	$	—	$	568,931

Summary of Information Regarding Changes in Fair Value of Assets Measured at Fair Value

The following table presents summary information regarding changes in the fair value of assets measured at fair value using Level 3 input.

	December 31, 2017		December 31, 2016
	(in thousands)
Balance, beginning of period	$	—	$	—
Transfer into Level 3		34		—
Balance, end of period	$	34	$	—