Investments (Mortgage Loans Age Analysis) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans Receivable, Gross, Commercial, Real Estate	$ 4,983,354	$ 4,413,171
Financing Receivable, Recorded Investment, Current	4,983,354	4,394,015
Financing Receivable, Recorded Investment, Past Due	0	19,156
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	0	17,100
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Past Due	$ 0	$ 2,056

Financing receivables that are current.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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