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Investment Securities - Schedule of Amortized Cost and Fair Value by Contractual Maturity of Available-For-Sale Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
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Schedule of Available-for-sale Securities [Line Items] |  |
Fair Value | $ 297,573 | $ 307,019
U.S. Treasury and government sponsored entities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Within 1 year, amortized cost | 97,714 |
1-5 years, amortized cost | 147,715 |
Amortized Cost | 245,429 |
Within 1 year, fair value | 97,467 |
1-5 years, fair value | 145,851 |
Fair Value | $ 243,318 | 249,461
Within 1 year, weighted average yield | 1.08% |
1-5 years, weighted average yield | 1.71% |
Weighted Average Yield | 1.46% |
Corporate bonds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Within 1 year, amortized cost | $ 2,000 |
1-5 years, amortized cost | 21,703 |
5-10 years, amortized cost | 10,449 |
Amortized Cost | 34,152 |
Within 1 year, fair value | 2,000 |
1-5 years, fair value | 21,891 |
5-10 years, fair value | 10,578 |
Fair Value | $ 34,469 | 37,132
Within 1 year, weighted average yield | 2.37% |
1-5 years, weighted average yield | 2.63% |
5-10 years, weighted average yield | 3.05% |
Weighted Average Yield | 2.74% |
Collateralized loan obligations |  |
Schedule of Available-for-sale Securities [Line Items] |  |
1-5 years, amortized cost | $ 3,000 |
Over 10 years, amortized cost | 3,000 |
Amortized Cost | 6,000 |
1-5 years, fair value | 2,999 |
Over 10 years, fair value | 3,011 |
Fair Value | $ 6,010 | 6,005
1-5 years, weighted average yield | 3.04% |
Over 10 years, weighted average yield | 3.51% |
Weighted Average Yield | 3.27% |
Preferred stock |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Over 10 years, amortized cost | $ 5,373 |
Amortized Cost | 5,373 |
Over 10 years, fair value | 5,527 |
Fair Value | $ 5,527 |
Over 10 years, weighted average yield | 6.36% |
Weighted Average Yield | 6.36% |
Municipal securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Within 1 year, amortized cost | $ 3,202 |
1-5 years, amortized cost | 10,603 |
Amortized Cost | 13,805 |
Within 1 year, fair value | 3,198 |
1-5 years, fair value | 10,578 |
Fair Value | $ 13,776 | $ 14,421
Within 1 year, weighted average yield | 1.80% |
1-5 years, weighted average yield | 2.67% |
Weighted Average Yield | 2.47% |

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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 + Details
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 + Details
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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