Changes in Accumulated Other Comprehensive Income by Component - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Accumulated other comprehensive income
Beginning balance	$ 488,304	$ 449,687	$ 480,461	$ 460,305
Other comprehensive (loss) income before reclassifications			(1,421)	1,925
(Gains) losses reclassified from other comprehensive income			(161)	71
Net current period other comprehensive (loss) income			(1,582)	1,996
Ending balance	480,205	464,750	480,205	464,750
Realized gain			200
Realized loss				100
Changes in other comprehensive (loss) income, tax expense (benefit)			(400)	500
Accumulated Other Comprehensive Income, net of taxes
Accumulated other comprehensive income
Beginning balance	4,995	4,042	5,563	2,919
Ending balance	$ 3,981	$ 4,915	$ 3,981	$ 4,915

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details