Investments (Net Realized Gains (Losses) on Disposals) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items]
HTM fixed income securities Gains	$ 0	$ 2
HTM fixed income securities Losses	0	0
Equity securities Gains	2,280	8,399
Equity securities Losses	0	(330)
Short-term investments Gains	14	1
Short-term investments Losses	0	(4)
Other investments Gains	7	0
Other investments Losses	0	0
Net realized investment gains on disposals	3,444	4,731
Proceeds from sale of fixed income securities, AFS	218,411	675,396
Proceeds from sale of equity securities	3,721	40,740
Fixed Maturities [Member]
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items]
AFS securities Gains	1,844	2,623
AFS securities Losses	(701)	(5,960)
Equity Securities [Member]
Schedule of Realized Gains (Losses) on Disposals Excluding OTTI [Line Items]
Net realized investment gains on disposals	$ 2,280	$ 8,069

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The cash inflow associated with the sale of equity securities.

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Gross realized gains on short term investments.

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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