Acquisitions - Consideration Paid and Allocation of Purchase Price to Net Assets Acquired (Details) - USD ($)	Jun. 30, 2017	Jun. 30, 2016	Jun. 16, 2017	Dec. 31, 2016
Allocation of total consideration paid:
Goodwill	$ 1,800,741,933			$ 551,593,796
Avenue Financial Holdings, Inc. (Avenue)
Equity consideration:
Total equity consideration		$ 182,469,000
Non-equity consideration:
Cash paid to redeem common stock		20,910,000
Cash paid to exchange outstanding stock options		987,000
Allocation of total consideration paid:
Fair value of net assets assumed including identifiable intangible assets		81,695,000
Goodwill		122,671,000
Total consideration paid		$ 204,366,000
Avenue Financial Holdings, Inc. (Avenue) | Common Stock
Equity consideration:
Common stock issued (in shares)		3,760,326
Total equity consideration		$ 182,469,000
BNC Bancorp
Equity consideration:
Total equity consideration	1,858,133,000
Non-equity consideration:
Cash paid to redeem common stock	129,000
Allocation of total consideration paid:
Fair value of net assets assumed including identifiable intangible assets	609,068,000		$ 609,068,000
Goodwill	1,249,194,000
Total consideration paid	$ 1,858,262,000
BNC Bancorp | Common Stock
Equity consideration:
Common stock issued (in shares)	27,687,100
Total equity consideration	$ 1,858,133,000