Liability for Unpaid Claims - Summary of Liability for Unpaid Health Claims (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Incurred related to:
Total incurred	$ 570,107	$ 611,117	$ 552,630
Health premium
Activity in the Liability for Unpaid Health Claims
Beginning balance	163,808	154,528	146,865
Incurred related to:
Current year	584,936	612,305	555,647
Prior years	(14,829)	(1,188)	(3,017)
Paid related to:
Current year	442,127	470,426	424,633
Prior year	129,527	131,411	120,334
Total paid	571,654	601,837	544,967
Ending balance	$ 162,261	$ 163,808	$ 154,528

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Amount, after effects of reinsurance, of payments to settle claims incurred in the current period and related claims settlement costs.

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Amount, after effects of reinsurance, of payments to settle claims incurred in prior periods and related claims settlement costs.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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Amount, after effects of reinsurance, of payments to settle insured claims and pay costs incurred in the claims settlement process.

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Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs.

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