Fair Value of Financial Instruments - Recurring Level III Assets (Details) - Level III - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
December 31, 2017	$ 31,448	$ 8,583	$ 25,235	$ 7,981
Realized and unrealized gains included in earnings	(31)	(245)	918	303
Purchase of securities	2,000		8,232
Unrealized gain included in other comprehensive income (loss)	1,787	0	1,541	54
Unrealized loss included in other comprehensive income (loss)	(636)		(1,358)
September 30, 2018	34,568	8,338	34,568	8,338
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
December 31, 2017	900	300	900	300
Realized and unrealized gains included in earnings	672	0	672	0
Purchase of securities	2,000		2,000
Unrealized gain included in other comprehensive income (loss)	0	0	0	0
Unrealized loss included in other comprehensive income (loss)	0		0
September 30, 2018	3,572	300	3,572	300
Loans receivable \| Interest rate lock commitment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
December 31, 2017	2,375	2,094	1,426	1,546
Realized and unrealized gains included in earnings	(703)	(245)	246	303
Purchase of securities	0		0
Unrealized gain included in other comprehensive income (loss)	0	0	0	0
Unrealized loss included in other comprehensive income (loss)	0		0
September 30, 2018	1,672	1,849	1,672	1,849
Total debt securities \| Municipal Bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
December 31, 2017	28,173	6,189	22,909	6,135
Realized and unrealized gains included in earnings	0	0	0	0
Purchase of securities	0		6,232
Unrealized gain included in other comprehensive income (loss)	1,787	0	1,541	54
Unrealized loss included in other comprehensive income (loss)	(636)		(1,358)
September 30, 2018	$ 29,324	$ 6,189	$ 29,324	$ 6,189

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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