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Consolidation Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2012 | Sep. 30, 2012 | Jun. 30, 2012 | Mar. 31, 2012 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Net income | $ 25,335 | $ 32,653 | $ 27,122 | $ 21,308 | $ 1,308 | $ 18,274 | $ 288 | $ 18,093 | $ 106,418 | $ 37,963 | $ 22,033
Unrealized holding (losses) gains arising during period |  |  |  |  |  |  |  |  | (54,557) | 30,937 | 45,592
Non-credit portion of other-than-temporary impairments recognized in other comprehensive income |  |  |  |  |  |  |  |  | 50 | 1,660 | 772
Amount reclassified into net income: Held-to-maturity securities |  |  |  |  |  |  |  |  | (1,025) | (1,581) | (1,484)
Realized gains on available for sale securities |  |  |  |  |  |  |  |  | (15,301) | (6,118) | (1,821)
Total unrealized (losses) gains on investment securities |  |  |  |  |  |  |  |  | (70,824) | 25,080 | 43,380
Amount reclassified into net income: Net actuarial loss |  |  |  |  |  |  |  |  | 2,843 | 3,837 | 2,712
Amount reclassified into net income: Prior service cost |  |  |  |  |  |  |  |  | 6 | 97 | 97
Amount reclassified into net income: Curtailment expense |  |  |  |  |  |  |  |  | 11 | 0 | 0
Total defined benefit pension and post-retirement plans |  |  |  |  |  |  |  |  | 41,635 | (13,334) | (8,110)
Other comprehensive (loss) income | 7,768 | (2,195) | (62,643) | 27,881 | (30,971) | 26,507 | 5,520 | 10,690 |  |  |
Comprehensive income | 33,103 | 30,458 | (35,521) | 49,189 | (29,663) | 44,781 | 5,808 | 28,783 | 77,229 | 49,709 | 57,303
Accumulated Other-than-Temporary Impairment [Member] |  |  |  |  |  |  |  |  |  |  |
Amounts reclassified into net income: Non-credit other-than-temporary impairment |  |  |  |  |  |  |  |  | 9 | 182 | 321
Other comprehensive (loss) income |  |  |  |  |  |  |  |  | 59 | 1,842 |
Accumulated Defined Benefit Plans Adjustment [Member] |  |  |  |  |  |  |  |  |  |  |
Net actuarial gain (loss) |  |  |  |  |  |  |  |  | 38,775 | (17,268) | (10,919)
Total defined benefit pension and post-retirement plans |  |  |  |  |  |  |  |  | 2,860 | 3,934 |
Accumulated other comprehensive income (loss) [Member] |  |  |  |  |  |  |  |  |  |  |
Amounts reclassified into net income: Non-credit other-than-temporary impairment |  |  |  |  |  |  |  |  | (13,457) | (3,583) |
Other comprehensive (loss) income |  |  |  |  |  |  |  |  | $ (29,189) | $ 11,746 | $ 35,270

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