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Acquisitions - The Banc Ed Corp. (Details) $ / shares in Units, $ in Thousands, shares in Millions |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 31, 2019 USD ($) | Jan. 31, 2019 USD ($) $ / shares shares | Jul. 02, 2017 $ / shares | Dec. 31, 2019 USD ($) $ / shares | Dec. 31, 2018 USD ($) $ / shares | Dec. 31, 2017 USD ($)
Merger agreement |  |  |  |  |  |
Per share cash consideration entitled (in dollars per share) | $ / shares |  |  | $ 1.35 |  |  |
(Decrease) increase in other liabilities |  |  |  | $ (7,380) | $ 2,195 | $ (4,193)
Consideration paid |  |  |  |  |  |
Goodwill |  |  |  | 311,536 | 267,685 |
Banc Ed |  |  |  |  |  |
Merger agreement |  |  |  |  |  |
Share consideration conversion ratio |  | 8.2067 |  |  |  |
Per share cash consideration entitled (in dollars per share) | $ / shares |  | $ 111.53 |  |  |  |
Number of common shares issued for acquisition | shares |  | 6.7 |  |  |  |
Market value of common stock issued |  | $ 166,500 |  |  |  |
Adjustments to the fair value assigned to various assets and liabilities | $ 5,200 |  |  |  |  |
Common stock |  | $ 166,515 |  |  |  |
Share price | $ / shares |  | $ 24.76 |  |  |  |
Reversal of a deferred tax liability |  |  |  | 4,600 |  |
Transaction costs |  |  |  | 2,300 |  |
Assets acquired: |  |  |  |  |  |
Cash and cash equivalents |  | $ 42,013 |  |  |  |
Securities |  | 692,716 |  |  |  |
Loans held for sale |  | 2,157 |  |  |  |
Portfolio loans |  | 873,336 |  |  |  |
Premises and equipment |  | 32,156 |  |  |  |
Other intangible assets |  | 32,617 |  |  |  |
Mortgage servicing rights |  | 6,946 |  |  |  |
Other assets |  | 57,332 |  |  |  |
Total assets acquired |  | 1,739,273 |  |  |  |
Liabilities assumed: |  |  |  |  |  |
Deposits |  | 1,439,203 |  |  |  |
Other borrowings |  | 63,439 |  |  |  |
Other liabilities |  | 20,153 |  |  |  |
Total liabilities assumed |  | 1,522,795 |  |  |  |
Net assets acquired |  | 216,478 |  |  |  |
Consideration paid |  |  |  |  |  |
Cash |  | 91,400 |  |  |  |
Common stock |  | 166,515 |  |  |  |
Total consideration paid |  | 257,915 |  |  |  |
Goodwill |  | 41,437 |  |  |  |
Aggregate principal outstanding |  | 889,300 |  |  |  |
Fair value of performing loans, including loans held for sale |  | 871,000 |  |  |  |
Amount expected to be accreted, gross |  | 17,000 |  |  |  |
Contractual amount of PCI loans |  | 3,900 |  |  |  |
Accretable discount on PCI loans |  | 200 |  |  |  |
Fair value of credit-impaired loans |  | $ 2,300 |  | 1,300 |  |
Banc Ed | Pro Forma |  |  |  |  |  |
Consideration paid |  |  |  |  |  |
Total revenues (net interest income plus non-interest income) |  |  |  | 409,324,000 | 411,633,000 |
Net income |  |  |  | $ 113,640,000 | $ 118,361,000 |
Diluted earnings per common share (in dollars per share) | $ / shares |  |  |  | $ 2.03 | $ 2.15 |
Banc Ed | Non-interest expense |  |  |  |  |  |
Merger agreement |  |  |  |  |  |
Business acquisition expenses |  |  |  | $ 13,700 | $ 400 |
IST | Non-interest expense |  |  |  |  |  |
Merger agreement |  |  |  |  |  |
Business acquisition expenses |  |  |  | $ 900 |  |

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