Fair Value of Financial Instruments (Carrying Value and Estimated Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investments
Available-for-sale securities	$ 1,703,319	$ 1,749,488
Trading securities	17,143	13,240
Equity securities	283,178	248,361
Mortgage loans	36,374	25,782
Fair Value
Investments
Equity securities	283,178	248,361
Mortgage loans	38,018	26,021
Other long-term investments	47,772	37,077
Short-term investments	175	175
Cash and cash equivalents	148,784	64,454
Corporate-owned life insurance	5,976	4,907
Carrying Value
Investments
Equity securities	283,178	248,361
Mortgage loans	36,374	25,782
Other long-term investments	47,772	37,077
Short-term investments	175	175
Cash and cash equivalents	148,784	64,454
Corporate-owned life insurance	5,976	4,907
Fixed Maturities \| Fair Value
Investments
Available-for-sale securities	1,703,319	1,749,488
Trading securities	17,143	13,240
Fixed Maturities \| Carrying Value
Investments
Available-for-sale securities	1,703,319	1,749,488
Trading securities	$ 17,143	$ 13,240

Other Long-term Investments, Fair Value Disclosure

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Short-term Investments, Fair Value Disclosure

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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