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Deposits (Tables) | 3 Months Ended
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Mar. 31, 2019
Banking and Thrift [Abstract] |
Deposit Account Balances | Deposits account balances are summarized as follows (in thousands):
| March 31, 2019 |  | December 31, 2018
Non-interest-bearing demand | $ | 380,681 |  |  | $ | 395,375 |
Interest-bearing negotiable orders of withdrawal (NOW) | 529,610 |  |  | 458,012 |
Savings and money market | 1,400,522 |  |  | 1,336,229 |
Certificates of deposit | 1,064,392 |  |  | 1,096,896 |
Total deposits | $ | 3,375,205 |  |  | $ | 3,286,512 |
Interest Expense on Deposits | Interest expense on deposit accounts is summarized for the periods indicated (in thousands):
| Three Months Ended March 31,
| 2019 |  | 2018
Negotiable orders of withdrawal, savings, and money market | $ | 4,794 |  |  | $ | 2,143 |
Certificates of deposit | 5,453 |  |  | 3,068 |
Total interest expense on deposit accounts | $ | 10,247 |  |  | $ | 5,211 |

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