Shareholders' Equity (AOCI Reclassification) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Reclassifications from AOCI to net income:
Tax effect, calculated using the 21% federal statutory tax rate	$ 4	$ (508)
Net reclassification adjustments	(13)	1,909
Deferred tax expense (benefit) included in OCI	6,804	(7,060)
Realized investment gains (losses)
Reclassifications from AOCI to net income:
Reclassifications from AOCI to net income:	$ (17)	$ 2,417

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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