Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Unrecognized tax benefits
Unrecognized tax benefits, beginning of year	$ 1,960	$ 2,008
Tax positions taken during the current year - Increases	5,671
Tax positions taken during a prior year - Increases	96	75
Decreases for settlements during the period		(123)
Reductions for lapses of applicable statute of limitations	(954)
Unrecognized tax benefits, end of year	6,773	1,960
Amount of unrecognized tax benefit, if recognized, that would affect the effective tax rate	6,773	1,960
Interest accrued on unrecognized tax benefit	153	217
Penalties accrued on unrecognized tax benefit	$ 0	$ 0

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

No definition available.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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