Interest-bearing Deposits and Securities: Schedule of Available for Sale Securities Amortized Cost and Fair Value by Contractual Maturity (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Mortgage Backed Securities Contractual Maturity
Available for Sale Securities Amortized Cost Contractual Maturity	$ 135,790	$ 91,281
Available for Sale Securities Fair Value Contractual Maturity	137,844	93,254
Due in one year or less
Available for Sale Securities Amortized Cost Contractual Maturity	30,087	19,520
Available for Sale Securities Fair Value Contractual Maturity	30,158	19,602
Due after one year through five years
Available for Sale Securities Amortized Cost Contractual Maturity	208,232	312,862
Available for Sale Securities Fair Value Contractual Maturity	209,261	313,930
Due after five years through ten years
Available for Sale Securities Amortized Cost Contractual Maturity	37,705	38,916
Available for Sale Securities Fair Value Contractual Maturity	37,720	39,009
Due after ten years through twenty years
Available for Sale Securities Amortized Cost Contractual Maturity	21,237
Available for Sale Securities Fair Value Contractual Maturity	21,147
Total by contractual maturity before mortgage-backed and equity securities
Available for Sale Securities Amortized Cost Contractual Maturity	297,261	371,298
Available for Sale Securities Fair Value Contractual Maturity	298,286	372,541
Total by contractual maturity
Available for Sale Securities Amortized Cost Contractual Maturity	433,051	462,579
Available for Sale Securities Fair Value Contractual Maturity	$ 436,130	$ 465,795