Covered Assets and Indemnification Asset - Impaired Loans (Details) - Covered - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Impaired loans
Unpaid Contractual Principal Balance	$ 311,560		$ 335,091
Recorded Investment with No Allowance	105,861		110,101
Recorded Investment with Allowance	16,709		27,572
Total Recorded Investment	122,570		137,673
Related Allowance	710		344
Average investment in covered impaired loans
Average investment	130,122	$ 214,062
Non-accrual loans
Non-accrual loans	3,678		3,836
Interest income recorded	100
Secured
Average investment in covered impaired loans
Average investment	1,023	5,509
Non-accrual loans
Non-accrual loans	52		52
Unsecured
Average investment in covered impaired loans
Average investment	236	1,786
Secured by Commercial Properties
Average investment in covered impaired loans
Average investment	48,965	92,941
Non-accrual loans
Non-accrual loans	302		730
Secured by Residential Properties
Average investment in covered impaired loans
Average investment	75,983	95,788
Non-accrual loans
Non-accrual loans	3,294		3,035
Residential Construction Loans
Average investment in covered impaired loans
Average investment		673
Commercial construction loans and land development
Average investment in covered impaired loans
Average investment	3,915	$ 17,365
Non-accrual loans
Non-accrual loans	30		19
PCI loans
Impaired loans
Unpaid Contractual Principal Balance	306,635		330,444
Recorded Investment with No Allowance	101,684		106,182
Recorded Investment with Allowance	16,709		27,572
Total Recorded Investment	118,393		133,754
Related Allowance	710		344
Non-accrual loans
Non-accrual loans	0		400
PCI loans \| Secured
Impaired loans
Unpaid Contractual Principal Balance	5,350		10,579
Recorded Investment with No Allowance	537		1,024
Recorded Investment with Allowance	191		189
Total Recorded Investment	728		1,213
Related Allowance	7		13
PCI loans \| Unsecured
Impaired loans
Unpaid Contractual Principal Balance	6,908		3,259
Recorded Investment with No Allowance	173		299
Total Recorded Investment	173		299
PCI loans \| Secured by Commercial Properties
Impaired loans
Unpaid Contractual Principal Balance	130,869		143,934
Recorded Investment with No Allowance	29,355		26,415
Recorded Investment with Allowance	15,326		26,222
Total Recorded Investment	44,681		52,637
Related Allowance	578		271
PCI loans \| Secured by Residential Properties
Impaired loans
Unpaid Contractual Principal Balance	142,319		148,384
Recorded Investment with No Allowance	69,043		73,240
Recorded Investment with Allowance	1,192		1,161
Total Recorded Investment	70,235		74,401
Related Allowance	125		60
PCI loans \| Residential Construction Loans
Impaired loans
Unpaid Contractual Principal Balance	879		766
PCI loans \| Commercial construction loans and land development
Impaired loans
Unpaid Contractual Principal Balance	20,310		23,522
Recorded Investment with No Allowance	2,576		5,204
Total Recorded Investment	2,576		5,204
Loans excluding PCI Loans
Impaired loans
Unpaid Contractual Principal Balance	4,925		4,647
Recorded Investment with No Allowance	4,177		3,919
Total Recorded Investment	4,177		3,919
Loans excluding PCI Loans \| Secured
Impaired loans
Unpaid Contractual Principal Balance	52		52
Recorded Investment with No Allowance	52		52
Total Recorded Investment	52		52
Loans excluding PCI Loans \| Secured by Commercial Properties
Impaired loans
Unpaid Contractual Principal Balance	392		396
Recorded Investment with No Allowance	302		310
Total Recorded Investment	302		310
Loans excluding PCI Loans \| Secured by Residential Properties
Impaired loans
Unpaid Contractual Principal Balance	4,445		4,175
Recorded Investment with No Allowance	3,793		3,537
Total Recorded Investment	3,793		3,537
Loans excluding PCI Loans \| Commercial construction loans and land development
Impaired loans
Unpaid Contractual Principal Balance	36		24
Recorded Investment with No Allowance	30		20
Total Recorded Investment	$ 30		$ 20

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