Fair Value Measurements - Summary of Fair Value, Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financial assets:
Equity securities at fair value	$ 9,651	$ 0
Equity securities at fair value	0	9,720
Securities held to maturity	304,036	303,716
Estimate of Fair Value Measurement
Financial assets:
Cash and cash equivalents	45,072	46,167
Equity securities at fair value	9,651
Equity securities at fair value		9,720
Securities held to maturity	295,472	299,114
Federal Home Loan Bank stock	10,730	12,105
Loans and loans held for sale, net	2,165,575	2,174,871
Accrued interest receivable	6,120	6,438
Financial liabilities:
Deposits	2,071,733	2,036,150
Borrowings	168,656	203,913
On-balance sheet derivative financial instruments:
Derivative liabilities:	16
Carrying Amount
Financial assets:
Cash and cash equivalents	45,072	46,167
Equity securities at fair value	9,651
Equity securities at fair value		9,720
Securities held to maturity	304,036	303,716
Federal Home Loan Bank stock	10,730	12,105
Loans and loans held for sale, net	2,190,155	2,195,139
Accrued interest receivable	6,120	6,438
Financial liabilities:
Deposits	2,077,838	2,039,869
Borrowings	170,000	205,000
On-balance sheet derivative financial instruments:
Derivative liabilities:	16
Level 1
Financial assets:
Cash and cash equivalents	45,072	46,167
Equity securities at fair value	9,651
Equity securities at fair value		9,720
Securities held to maturity	0	0
Federal Home Loan Bank stock	0	0
Loans and loans held for sale, net	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Borrowings	0	0
On-balance sheet derivative financial instruments:
Derivative liabilities:	0
Level 2
Financial assets:
Cash and cash equivalents	0	0
Equity securities at fair value	0
Equity securities at fair value		0
Securities held to maturity	295,472	299,114
Federal Home Loan Bank stock	0	0
Loans and loans held for sale, net	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Borrowings	168,656	203,913
On-balance sheet derivative financial instruments:
Derivative liabilities:	0
Level 3
Financial assets:
Cash and cash equivalents	0	0
Equity securities at fair value	0
Equity securities at fair value		0
Securities held to maturity	0	0
Federal Home Loan Bank stock	10,730	12,105
Loans and loans held for sale, net	2,165,575	2,174,871
Accrued interest receivable	6,120	6,438
Financial liabilities:
Deposits	2,071,733	2,036,150
Borrowings	0	0
On-balance sheet derivative financial instruments:
Derivative liabilities:	16
Interest rate swap agreements | Estimate of Fair Value Measurement
On-balance sheet derivative financial instruments:
Derivative assets:	13,350	8,766
Derivative liabilities:	13,338	8,785
Interest rate swap agreements | Carrying Amount
On-balance sheet derivative financial instruments:
Derivative assets:	13,350	8,766
Derivative liabilities:	13,338	8,785
Interest rate swap agreements | Level 1
On-balance sheet derivative financial instruments:
Derivative assets:	0	0
Derivative liabilities:	0	0
Interest rate swap agreements | Level 2
On-balance sheet derivative financial instruments:
Derivative assets:	13,350	8,766
Derivative liabilities:	13,338	8,785
Interest rate swap agreements | Level 3
On-balance sheet derivative financial instruments:
Derivative assets:	0	0
Derivative liabilities:	0	0
Mortgage loan commitments best efforts | Estimate of Fair Value Measurement
On-balance sheet derivative financial instruments:
Derivative assets:	206
Mortgage loan commitments best efforts | Carrying Amount
On-balance sheet derivative financial instruments:
Derivative assets:	206
Mortgage loan commitments best efforts | Level 1
On-balance sheet derivative financial instruments:
Derivative assets:	0
Mortgage loan commitments best efforts | Level 2
On-balance sheet derivative financial instruments:
Derivative assets:	0
Mortgage loan commitments best efforts | Level 3
On-balance sheet derivative financial instruments:
Derivative assets:	206
Mortgage loan commitments mandatory delivery | Estimate of Fair Value Measurement
On-balance sheet derivative financial instruments:
Derivative assets:	171
Mortgage loan commitments mandatory delivery | Carrying Amount
On-balance sheet derivative financial instruments:
Derivative assets:	171
Mortgage loan commitments mandatory delivery | Level 3
On-balance sheet derivative financial instruments:
Derivative assets:	171
Mortgage loan commitments-best efforts | Estimate of Fair Value Measurement
On-balance sheet derivative financial instruments:
Derivative assets:		210
Derivative liabilities:		36
Mortgage loan commitments-best efforts | Carrying Amount
On-balance sheet derivative financial instruments:
Derivative assets:		210
Derivative liabilities:		36
Mortgage loan commitments-best efforts | Level 1
On-balance sheet derivative financial instruments:
Derivative assets:		0
Derivative liabilities:		0
Mortgage loan commitments-best efforts | Level 2
On-balance sheet derivative financial instruments:
Derivative assets:		0
Derivative liabilities:		0
Mortgage loan commitments-best efforts | Level 3
On-balance sheet derivative financial instruments:
Derivative assets:		210
Derivative liabilities:		36
Forward loan sale commitments best efforts | Estimate of Fair Value Measurement
On-balance sheet derivative financial instruments:
Derivative assets:	30	22
Derivative liabilities:	66	69
Forward loan sale commitments best efforts | Carrying Amount
On-balance sheet derivative financial instruments:
Derivative assets:	30	22
Derivative liabilities:	66	69
Forward loan sale commitments best efforts | Level 1
On-balance sheet derivative financial instruments:
Derivative assets:	0	0
Derivative liabilities:	0	0
Forward loan sale commitments best efforts | Level 2
On-balance sheet derivative financial instruments:
Derivative assets:	0	0
Derivative liabilities:	0	0
Forward loan sale commitments best efforts | Level 3
On-balance sheet derivative financial instruments:
Derivative assets:	30	22
Derivative liabilities:	66	$ 69
Forward loan sale commitments mandatory delivery | Estimate of Fair Value Measurement
On-balance sheet derivative financial instruments:
Derivative liabilities:	55
Forward loan sale commitments mandatory delivery | Carrying Amount
On-balance sheet derivative financial instruments:
Derivative liabilities:	55
Forward loan sale commitments mandatory delivery | Level 1
On-balance sheet derivative financial instruments:
Derivative liabilities:	0
Forward loan sale commitments mandatory delivery | Level 2
On-balance sheet derivative financial instruments:
Derivative liabilities:	0
Forward loan sale commitments mandatory delivery | Level 3
On-balance sheet derivative financial instruments:
Derivative liabilities:	$ 55