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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Net income | $ 41,426 | $ 43,601 | $ 91,866 | $ 80,633
Unrealized holding gains arising during period | 23,326 | 36,188 | 40,087 | 78,917
Non-Credit Portion of Other-Than-Temporary Impairments Recognized in Other Comprehensive Income | 4 | (6) | 4 | (6)
Amounts reclassified into net income: Held-to-maturity securities | (28) | (12) | (60) | (59)
Amounts reclassified into net income: Realized (gains) losses on available-for-sale securities | (1,225) | (1,145) | (244) | 609
Total unrealized gains on investment securities | 22,077 | 35,025 | 39,787 | 79,461
Amount reclassified into net income: Net actuarial loss | 330 | 985 | 660 | 1,971
Total defined benefit pension and post-retirement plans | 330 | 985 | 660 | 1,971
Other comprehensive income | 22,407 | 36,010 | 40,447 | 81,432
Comprehensive income | $ 63,833 | $ 79,611 | $ 132,313 | $ 162,065

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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=51831270 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Comprehensive Income -URI http://asc.fasb.org/extlink&oid=51831223 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e557-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=51831255 + Details
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