Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

Financial Asset and Liabilities Measured at Fair Value on Recurring Basis

The Company has segregated all financial assets and liabilities that are measured at fair value on a recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to estimate the fair value at the measurement date in the tables below. See Note 1, Summary of Significant Accounting Policies, in the Annual Report on Form 10-K for the year ended December 31, 2017, for a description of how fair value measurements are determined.

	March 31, 2018
(Dollars in thousands)	Level 1		Level 2		Level 3		Total
Assets
Securities available for sale	$	—	$	4,542,486	$	—	$	4,542,486
CRA and Community Development Investment Funds	—		9,801		—		9,801
Mortgage loans held for sale	—		110,348		—		110,348
Derivative instruments	—		17,072		—		17,072
Total	$	—	$	4,679,707	$	—	$	4,679,707
Liabilities
Derivative instruments	$	—	$	32,154	$	—	$	32,154
Total	$	—	$	32,154	$	—	$	32,154
	December 31, 2017
	Level 1		Level 2		Level 3		Total
Assets
Securities available for sale	$	—	$	4,590,062	$	—	$	4,590,062
Mortgage loans held for sale	—		134,916		—		134,916
Derivative instruments	—		31,265		—		31,265
Total	$	—	$	4,756,243	$	—	$	4,756,243
Liabilities
Derivative instruments	$	—	$	25,154	$	—	$	25,154
Total	$	—	$	25,154	$	—	$	25,154

Financial Asset and Liabilities Measured at Fair Value on Nonrecurring Basis

The Company has segregated all assets and liabilities that are measured at fair value on a non-recurring basis into the most appropriate level within the fair value hierarchy based on the inputs used to determine the fair value at the measurement date in the tables below.

	March 31, 2018
(Dollars in thousands)	Level 1		Level 2		Level 3		Total
Assets
Loans	$	—	$	—	$	85,269	$	85,269
OREO, net	—		—		2,234		2,234
Total	$	—	$	—	$	87,503	$	87,503
	December 31, 2017
(Dollars in thousands)	Level 1		Level 2		Level 3		Total
Assets
Loans	$	—	$	—	$	71,210	$	71,210
OREO, net	—		—		3,029		3,029
Total	$	—	$	—	$	74,239	$	74,239

Summary of Difference Between the Aggregate Fair Value and the Aggregate Unpaid Principal Balance for Mortgage Loans Held for Sale

The following table summarizes the difference between the aggregate fair value and the aggregate unpaid principal balance for mortgage loans held for sale measured at fair value:

	March 31, 2018						December 31, 2017
(Dollars in thousands)	Aggregate Fair Value		Aggregate Unpaid Principal		Aggregate Fair Value Less Unpaid Principal		Aggregate Fair Value		Aggregate Unpaid Principal		Aggregate Fair Value Less Unpaid Principal
Mortgage loans held for sale, at fair value	$	110,348	$	107,849	$	2,499	$	134,916	$	131,276	$	3,640