Investments Schedule of Available-for-sale and Held-to-Maturity Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Available-for-sale securities at fair value:
Amortized Cost	$ 960,550	$ 1,018,774
Unrealized Gains	11,580	2,437
Unrealized Losses	(5,399)	(27,146)
Fair Value	966,731	994,065
Held-to-maturity securities at amortized cost:
Amortized Cost	54,482	70,438
Unrealized Gains	24	2
Unrealized Losses	(577)	(1,845)
Fair Value	53,929	68,595
Equity securities at fair value:
Amortized Cost	19,092	14,228
Fair Value	19,092	14,228
U.S. government and agencies
Available-for-sale securities at fair value:
Amortized Cost	20,047	30,043
Unrealized Gains	8	0
Unrealized Losses	(114)	(929)
Fair Value	19,941	29,114
Held-to-maturity securities at amortized cost:
Amortized Cost		9,898
Unrealized Gains		2
Unrealized Losses		0
Fair Value		9,900
Government-sponsored entities
Available-for-sale securities at fair value:
Amortized Cost	181,442	211,655
Unrealized Gains	601	0
Unrealized Losses	(65)	(3,952)
Fair Value	181,978	207,703
Municipal bonds
Available-for-sale securities at fair value:
Amortized Cost	314,235	309,837
Unrealized Gains	10,002	2,223
Unrealized Losses	(92)	(3,101)
Fair Value	324,145	308,959
Mortgage-backed securities
Available-for-sale securities at fair value:
Amortized Cost	444,826	467,239
Unrealized Gains	969	214
Unrealized Losses	(5,128)	(19,164)
Fair Value	440,667	448,289
Held-to-maturity securities at amortized cost:
Amortized Cost	54,482	60,540
Unrealized Gains	24	0
Unrealized Losses	(577)	(1,845)
Fair Value	53,929	58,695
Money market mutual funds
Equity securities at fair value:
Amortized Cost	19,092	14,228
Fair Value	$ 19,092	$ 14,228

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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