Investment Securities - Schedule of Gross Unrealized Losses (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities [Line Items]
Fair Value, Less than 12 months	$ 410,397	$ 444,968
Unrealized Loss, Less than 12 months	6,294	9,409
Fair Value, 12 months or more	20,779	22,199
Unrealized Loss, 12 months or more	721	810
Fair Value, Total	431,176	467,167
Unrealized Losses, Total	7,015	10,219
Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Fair Value, Less than 12 months	410,397	444,968
Unrealized Loss, Less than 12 months	6,294	9,409
Fair Value, 12 months or more	17,746	19,073
Unrealized Loss, 12 months or more	591	675
Fair Value, Total	428,143	464,041
Unrealized Losses, Total	6,885	10,084
Debt Securities \| U.S. Government Agency Securities
Schedule Of Available For Sale Securities [Line Items]
Fair Value, Less than 12 months	990	985
Unrealized Loss, Less than 12 months	9	13
Fair Value, Total	990	985
Unrealized Losses, Total	9	13
Debt Securities \| Mortgage-backed Securities - Residential
Schedule Of Available For Sale Securities [Line Items]
Fair Value, Less than 12 months	366,265	390,595
Unrealized Loss, Less than 12 months	5,402	7,230
Fair Value, 12 months or more	17,527	19,073
Unrealized Loss, 12 months or more	580	675
Fair Value, Total	383,792	409,668
Unrealized Losses, Total	5,982	7,905
Debt Securities \| Municipals, Tax Exempt
Schedule Of Available For Sale Securities [Line Items]
Fair Value, Less than 12 months	32,832	43,132
Unrealized Loss, Less than 12 months	868	2,114
Fair Value, 12 months or more	219
Unrealized Loss, 12 months or more	11
Fair Value, Total	33,051	43,132
Unrealized Losses, Total	879	2,114
Debt Securities \| Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Fair Value, Less than 12 months	10,310	10,256
Unrealized Loss, Less than 12 months	15	52
Fair Value, Total	10,310	10,256
Unrealized Losses, Total	15	52
Equity Securities
Schedule Of Available For Sale Securities [Line Items]
Fair Value, 12 months or more	3,033	3,126
Unrealized Loss, 12 months or more	130	135
Fair Value, Total	3,033	3,126
Unrealized Losses, Total	$ 130	$ 135

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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Amount of unrealized loss on securities classified as available-for-sale.

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27337-111563

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This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27337-111563

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

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-Publisher FASB
-Name Accounting Standards Codification
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