Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2018

Fair Value Disclosures [Abstract]

Schedule of Assets Measured at Fair Value on Recurring Basis

At June 30, 2018, assets measured at fair value on a recurring basis are summarized below:

	June 30, 2018
	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
	(in thousands)
Financial instruments carried at fair value, classified as a part of:
Securities available-for-sale—fixed maturity:
States and political subdivisions	$	—	$	218,300	$	—	$	218,300
Corporate bonds		—		143,959		—		143,959
U.S. agency-based mortgage-backed securities		—		13,362		—		13,362
U.S. Treasury securities		65,141		—		—		65,141
Total securities available-for-sale—fixed maturity		65,141		375,621		—		440,762
Securities available-for-sale—equity:
Domestic common stock		13,588		—		2		13,590
Total available-for-sale	$	78,729	$	375,621	$	2	$	454,352

At December 31, 2017, assets measured at fair value on a recurring basis are summarized below:

	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

Schedule of Assets Measured at Amortized Cost

At June 30, 2018, assets measured at amortized cost are summarized below:

	June 30, 2018
	Level 1 Inputs		Level 2 Inputs		Level 3 Inputs		Total Fair Value
	(in thousands)
Securities held-to-maturity—fixed maturity:
States and political subdivisions	$	—	$	434,737	$	—	$	434,737
Corporate bonds		—		98,016		—		98,016
U.S. agency-based mortgage-backed securities		—		9,387		—		9,387
U.S. Treasury securities		7,095		—		—		7,095
Obligations of U.S. government agencies		—		56,662		—		56,662
Asset-backed securities		—		1,175		—		1,175
Total held-to-maturity	$	7,095	$	599,977	$	—	$	607,072

At December 31, 2017, assets measured at amortized cost are summarized below:

	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
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

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.

	Six Months Ended			Twelve Months Ended
	June 30, 2018			December 31, 2017
	(in thousands)
Balance, beginning of period	$	34		$	—
Transfer into Level 3		—			34
Unrealized loss on equity security		(32	)		—
Balance, end of period	$	2		$	34

Summary of Carrying Values and Corresponding Fair Values for Financial Instruments

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

	As of  June 30, 2018				As of  December 31, 2017
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
	(in thousands)
Assets:
Fixed maturity securities—held-to-maturity	$	605,877	$	607,072	$	629,668	$	639,309
Fixed maturity securities—available-for-sale		440,762		440,762		465,594		465,594
Equity securities		13,590		13,590		9,282		9,282
Short-term investments		106,811		106,811		25,770		25,770
Cash and cash equivalents		21,176		21,176		55,559		55,559