Business Combinations (Changes in Goodwill) (Details) - Ozark National Life Insurance Company - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019	Jan. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Gross goodwill as of beginning of year	$ 13,864	$ 0
Goodwill resulting from business acquisition	0	13,864
Gross goodwill, before impairments	13,864	13,864
Accumulated impairment as of beginning of year		0		$ 0
Current year impairments	0	0
Goodwill	$ 13,864	$ 13,864	$ 13,864

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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