Loans and the Allowance for Loan Losses - (Details 9) - Receivables Acquired with Deteriorated Credit Quality - USD ($) $ in Thousands		Jun. 30, 2016	Apr. 01, 2016	Dec. 31, 2015	Jul. 01, 2015
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		$ 317,959		$ 336,165
Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		28,405		66,973
Not Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		289,554		$ 269,192
Contractually-required principal and interest
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		445,931
Contractually-required principal and interest | Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		35,175
Contractually-required principal and interest | Not Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		410,756
Nonaccretable difference
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total	[1]	(83,789)
Nonaccretable difference | Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total	[1]	(4,539)
Nonaccretable difference | Not Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total	[1]	(79,250)
Cash flows expected to be collected
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		362,142
Cash flows expected to be collected | Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		30,636
Cash flows expected to be collected | Not Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total		331,506
Accretable yield
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total	[2]	(44,183)
Accretable yield | Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total	[2]	(2,231)
Accretable yield | Not Covered Loans
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total	[2]	$ (41,952)
Heritage Financial Group
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total					$ 1,130,070
Heritage Financial Group | Contractually-required principal and interest
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total					1,216,173
Heritage Financial Group | Nonaccretable difference
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total					14,260
Heritage Financial Group | Cash flows expected to be collected
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total					1,201,913
Heritage Financial Group | Accretable yield
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total					$ 71,843
KeyWorth Bank
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total			$ 272,330
KeyWorth Bank | Contractually-required principal and interest
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total			289,495
KeyWorth Bank | Nonaccretable difference
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total			3,848
KeyWorth Bank | Cash flows expected to be collected
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total			285,647
KeyWorth Bank | Accretable yield
Fair value of loans determined to be impaired and not to be impaired at the time of acquisition
Total			$ 13,317

[1] Represents contractual principal and interest cash flows of $79,942 and $35, respectively, not expected to be collected.

[2] Represents contractual interest payments of $1,727 expected to be collected and purchase discount of $42,456.