Shareholders' Equity - Regulatory Capital (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Capital conservation buffer
Capital conservation buffer (as a percent)	2.50%
Capital conservation buffer for 2016 (as a percent)	0.625%
Capital conservation buffer for 2017 (as a percent)	1.25%
Capital conservation buffer for 2018 (as a percent)	1.875%
Capital conservation buffer for 2019 (as a percent)	2.50%
Common Equity Tier I capital to risk-weighted assets:
2019 Minimum Common Equity Tier I Capital Ratio (as a percent)	7.00%
Phased-out rate of certain deferred tax assets and intangible assets	60.00%	40.00%
Tier I capital to average assets
2019 Minimum Leverage Ratio (as a percent)	6.50%
Tier I Risk-Based Capital
2019 Minimum Tier I Risk-based Capital Ratio (as a percent)	8.50%
Total Risk-Based Capital Ratio
2019 Minimum Total Risk-based Capital Ratio	10.50%
Minimum
Common Equity Tier I capital to risk-weighted assets:
CET I to risk-weighted assets	4.50%
Total Risk-Based Capital Ratio
Regulatory standard to be well capitalized (as a percent)	6.50%
Heritage Oaks Bank
Company's and the Bank's actual regulatory capital amounts and ratios
Regulatory standard to be adequately capitalized (as a percent)	8.625%
Common Equity Tier I capital to risk-weighted assets:
Actual Common Equity Tier I (as a percent)	11.91%	12.48%
Regulatory standard to be adequately capitalized (as a percent)	5.125%
Regulatory standard to be well capitalized (as a percent)	6.50%
Tier I capital to average assets
Regulatory standard to be adequately capitalized (as a percent)	4.00%
Regulatory standard to be well capitalized (as a percent)	5.00%
Actual Leverage ratio (as a percent)	9.20%	9.50%
Tier I Risk-Based Capital
Regulatory standard to be adequately capitalized (as a percent)	6.625%
Regulatory standard to be well capitalized (as a percent)	8.00%
Actual Tier I capital (as a percent)	11.91%	12.48%
Total Risk-Based Capital Ratio
Regulatory standard to be adequately capitalized (as a percent)	8.625%
Actual total risk based capital (as a percent)	13.13%	13.74%
Regulatory standard to be well capitalized (as a percent)	10.00%
Heritage Oaks Bancorp
Company's and the Bank's actual regulatory capital amounts and ratios
Regulatory standard to be adequately capitalized (as a percent)	8.625%
Common Equity Tier I capital to risk-weighted assets:
Actual Common Equity Tier I (as a percent)	12.16%	12.61%
Regulatory standard to be adequately capitalized (as a percent)	5.125%
Tier I capital to average assets
Regulatory standard to be adequately capitalized (as a percent)	4.00%
Actual Leverage ratio (as a percent)	9.80%	9.90%
Tier I Risk-Based Capital
Regulatory standard to be adequately capitalized (as a percent)	6.625%
Actual Tier I capital (as a percent)	12.69%	13.01%
Total Risk-Based Capital Ratio
Regulatory standard to be adequately capitalized (as a percent)	8.625%
Actual total risk based capital (as a percent)	13.91%	14.26%
Junior subordinated debentures
Tier I Risk-Based Capital
Actual, Capital Amount	$ 10.1	$ 10.0