Other Comprehensive Income (Loss) - Summary of Unrealized Gains and Losses on Available-for-Sale Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	$ 223,726	$ 212,508
Balance at end of period	228,184	215,257
Accumulated Net Investment Gain (Loss) Attributable to Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	5,009	3,657
Unrealized gains (losses) arising during the period	(5,945)	6,109
Reclassification of net realized gains during the period	(119)	(752)
Related deferred taxes	1,274	(1,124)
Net change	(4,790)	4,233
Balance at end of period	$ 219	$ 7,890

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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