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Securities Available-for-Sale - Amortized Cost and Fair Value of Available-for-Sale Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | $ 686,205 | $ 650,782
Fair Value | 693,487 | 660,963
Obligations of U.S. government corporations and agencies |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Due in one year or less, Amortized Cost | 52,594 |
Due after one year through five years, Amortized Cost | 201,450 |
Due after five years through ten years, Amortized Cost | 64,569 |
Due after ten years, Amortized Cost | 66,050 |
Available-for-sale Securities, Debt Maturities, Amortized Cost | 384,663 |
Due in one year or less, Fair Value | 52,696 |
Due after one year through five years, Fair Value | 203,513 |
Due after five years through ten years, Fair Value | 64,975 |
Due after ten years, Fair Value | 68,315 |
Fair Value, Debt securities | 389,499 |
Collateralized mortgage obligations of U.S. government corporations and agencies |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 130,046 | 128,458
Fair Value | 129,777 | 128,835
Residential mortgage-backed securities of U.S. government corporations and agencies |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 36,606 | 39,185
Fair Value | 37,358 | 40,125
Commercial mortgage-backed securities of U.S. government corporations and agencies |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 127,311 | 69,697
Fair Value | 125,604 | 69,204
Debt Securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 678,626 | 643,203
Fair Value | 682,238 | 651,294
Marketable equity securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Amortized Cost | 7,579 | 7,579
Fair Value | $ 11,249 | $ 9,669

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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=73527792&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=73527792&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=73527792&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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