Liability for Unpaid Claims - Summary of Liability for Unpaid Health Claims (Details) - Health premium - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Activity in the Liability for Unpaid Health Claims
Beginning balance	$ 163,808	$ 154,528
Incurred related to:
Current year	439,860	454,186
Prior years	(13,136)	(851)
Total incurred	426,724	453,335
Paid related to:
Current year	307,582	326,553
Prior year	123,066	123,803
Total paid	430,648	450,356
Ending balance	$ 159,884	$ 157,507

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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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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, 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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