Changes in Accumulated Other Comprehensive Income by Component - Summary (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Accumulated other comprehensive income
Beginning balance	$ 493,102	$ 438,179	$ 480,461	$ 460,305
Other comprehensive (loss) income before reclassifications			(405)	1,057
Losses reclassified from other comprehensive income			(163)	66
Net current period other comprehensive (loss) income			(568)	1,123
Ending balance	488,304	449,687	488,304	449,687
Realized gain			200
Realized loss				100
Changes in other comprehensive (loss) income, tax expense (benefit)			(600)	300
Accumulated Other Comprehensive Income, net of taxes
Accumulated other comprehensive income
Beginning balance	4,292	2,386	5,563	2,919
Ending balance	$ 4,995	$ 4,042	$ 4,995	$ 4,042

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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-Name Accounting Standards Codification
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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 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: 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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Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details