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Deposits (Tables) | 12 Months Ended
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Dec. 31, 2020
Schedule of deposits and related interest expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | 2020 | ​ | 2019 |
​ | ​ | (Dollars in Thousands) |
Deposits: |  | ​ |  |  | ​ |  | ​
Demand - non-interest bearing | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic | ​ | $ | 3,781,277 | ​ | $ | 2,815,835 | ​
Foreign | ​ |  | 934,537 | ​ |  | 730,070 | ​
Total demand non-interest bearing | ​ |  | 4,715,814 | ​ |  | 3,545,905 | ​
Savings and interest bearing demand | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic | ​ |  | 2,919,314 | ​ |  | 2,477,668 | ​
Foreign | ​ |  | 933,191 | ​ |  | 790,161 | ​
Total savings and interest bearing demand | ​ |  | 3,852,505 | ​ |  | 3,267,829 | ​
Time, certificates of deposit $100,000 or more | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic | ​ |  | 797,692 | ​ |  | 636,005 | ​
Foreign | ​ |  | 822,387 | ​ |  | 827,031 | ​
Less than $100,000 | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic | ​ |  | 291,473 | ​ |  | 302,620 | ​
Foreign | ​ |  | 241,989 | ​ |  | 246,644 | ​
Total time, certificates of deposit | ​ |  | 2,153,541 | ​ |  | 2,012,300 | ​
Total deposits | ​ | $ | 10,721,860 | ​ | $ | 8,826,034 | ​
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | 2020 | ​ | 2019 | ​ | 2018 |
​ | ​ | (Dollars in Thousands) |
Interest expense: |  | ​ |  |  | ​ |  |  | ​ |  | ​
Savings and interest bearing demand | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic |  | $ | 5,098 | ​ | $ | 13,462 | ​ | $ | 11,029 | ​
Foreign |  | ​ | 1,260 | ​ |  | 2,917 | ​ |  | 1,735 | ​
Total savings and interest bearing demand |  | ​ | 6,358 | ​ |  | 16,379 | ​ |  | 12,764 | ​
Time, certificates of deposit $100,000 or more | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic |  | ​ | 8,827 | ​ |  | 7,804 | ​ |  | 4,741 | ​
Foreign |  | ​ | 7,536 | ​ |  | 9,407 | ​ |  | 5,798 | ​
Less than $100,000 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Domestic |  | ​ | 1,781 | ​ |  | 2,232 | ​ |  | 1,589 | ​
Foreign |  | ​ | 1,086 | ​ |  | 1,527 | ​ |  | 968 | ​
Total time, certificates of deposit |  | ​ | 19,230 | ​ |  | 20,970 | ​ |  | 13,096 | ​
Total interest expense on deposits | ​ | $ | 25,588 | ​ | $ | 37,349 | ​ | $ | 25,860 | ​
​
Scheduled maturities of time deposits | Scheduled maturities of time deposits as of December 31, 2020 were as follows: ​
​ | ​ | ​ | ​ | ​
​ |  | Total |
​ | ​ | (in thousands) |
2021 | ​ | $ | 1,971,433 | ​
2022 | ​ |  | 141,388 | ​
2023 | ​ |  | 28,781 | ​
2024 | ​ |  | 11,205 | ​
2025 | ​ |  | 681 | ​
Thereafter | ​ |  | 53 | ​
Total | ​ | $ | 2,153,541 | ​
Scheduled maturities of time deposits in amounts of $100,000 or more | ​
​ | ​ | ​ | ​
​ | ​ | Total
​ | ​ | (in thousands)
Due within 3 months or less |  | $ | 606,807
Due after 3 months and within 6 months | ​ |  | 385,859
Due after 6 months and within 12 months | ​ |  | 498,626
Due after 12 months | ​ |  | 129,792
​ | ​ | $ | 1,621,084

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