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Carrying Amount and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Carrying Amount |  |
Financial assets |  |
Cash and cash equivalents | $ 451,048 | $ 200,004
Investment securities, available-for-sale | 2,154,845 | 1,778,243
Investment securities, held-to-maturity | 634,413 | 648,313
Loans held for sale, at fair value | 37,058 | 38,833
Loans receivable, net of ALLL | 7,542,422 | 6,448,256
Accrued interest receivable | 54,376 | 44,462
Non-marketable equity securities | 21,910 | 29,884
Total financial assets | 10,896,072 | 9,187,995
Financial liabilities |  |
Deposits | 9,418,845 | 7,579,747
FHLB advances | 155,057 | 353,995
Repurchase agreements and other borrowed funds | 403,998 | 370,797
Subordinated debentures | 134,061 | 126,135
Accrued interest payable | 3,740 | 3,450
Interest rate swaps | 4,110 | 9,389
Total financial liabilities | 10,119,811 | 8,443,513
Estimated Fair Value | Level 1 |  |
Financial assets |  |
Cash and cash equivalents | 451,048 | 200,004
Investment securities, available-for-sale | 0 | 0
Investment securities, held-to-maturity | 0 | 0
Loans held for sale, at fair value | 0 | 0
Loans receivable, net of ALLL | 0 | 0
Accrued interest receivable | 54,376 | 44,462
Non-marketable equity securities | 0 | 0
Total financial assets | 505,424 | 244,466
Financial liabilities |  |
Deposits | 8,318,277 | 6,602,445
FHLB advances | 0 | 0
Repurchase agreements and other borrowed funds | 0 | 0
Subordinated debentures | 0 | 0
Accrued interest payable | 3,740 | 3,450
Interest rate swaps | 0 | 0
Total financial liabilities | 8,322,017 | 6,605,895
Estimated Fair Value | Level 2 |  |
Financial assets |  |
Cash and cash equivalents | 0 | 0
Investment securities, available-for-sale | 2,154,845 | 1,778,243
Investment securities, held-to-maturity | 634,380 | 660,086
Loans held for sale, at fair value | 37,058 | 38,833
Loans receivable, net of ALLL | 0 | 6,219,515
Accrued interest receivable | 0 | 0
Non-marketable equity securities | 21,910 | 29,884
Total financial assets | 2,848,193 | 8,726,561
Financial liabilities |  |
Deposits | 1,102,380 | 978,803
FHLB advances | 153,483 | 352,886
Repurchase agreements and other borrowed funds | 403,994 | 370,797
Subordinated debentures | 112,189 | 98,023
Accrued interest payable | 0 | 0
Interest rate swaps | 4,110 | 9,389
Total financial liabilities | 1,776,156 | 1,809,898
Estimated Fair Value | Level 3 |  |
Financial assets |  |
Cash and cash equivalents | 0 | 0
Investment securities, available-for-sale | 0 | 0
Investment securities, held-to-maturity | 0 | 0
Loans held for sale, at fair value | 0 | 0
Loans receivable, net of ALLL | 7,502,161 | 114,771
Accrued interest receivable | 0 | 0
Non-marketable equity securities | 0 | 0
Total financial assets | 7,502,161 | 114,771
Financial liabilities |  |
Deposits | 0 | 0
FHLB advances | 0 | 0
Repurchase agreements and other borrowed funds | 0 | 0
Subordinated debentures | 0 | 0
Accrued interest payable | 0 | 0
Interest rate swaps | 0 | 0
Total financial liabilities | $ 0 | $ 0

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