Long-Term Debt - Schedule of long-Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	$ 51,000	$ 100,500
2016	26,000	51,000
2017	351,000	26,000
2018	125,049	351,000
2019	75,333	125,062
2020		25,415
Thereafter	176,161	151,330
Total long-term debt, excluding prepayment penalty	804,543	830,307
Prepayment penalty	17,941	19,766
Total long-term debt	786,602us-gaap_LongTermDebt	810,541us-gaap_LongTermDebt
Long-term Debt, Fiscal Year Maturity, Average Rate [Abstract] [Abstract]
2015	2.00%	1.51%
2016	0.92%	2.00%
2017	1.68%	0.92%
2018	2.11%	1.99%
2019	1.97%	2.11%
2020		1.94%
Long-term Debt, Maturities, Repayments of Principal after Year Five	176,161
Thereafter		3.33%
Average rate, total, excluding prepayment penalty	2.09%	2.16%
Average rate, total	2.89%prk_AverageRate	2.79%prk_AverageRate
Long Term Debt Maturities Average Rate In After Year Five	3.16%
FHLB Advances
Long-term Debt, Fiscal Year Maturity [Abstract]
2015	51,000	100,500
2016	26,000	51,000
2017	51,000	26,000
2018	125,049	51,000
2019	75,333	125,062
2020		25,415
Thereafter		151,330
Total long-term debt, excluding prepayment penalty	504,543	530,307
Long-term Debt, Fiscal Year Maturity, Average Rate [Abstract] [Abstract]
2015	2.00%	1.51%
2016	0.92%	2.00%
2017	1.28%	0.92%
2018	2.11%	3.37%
2019	1.97%	2.11%
2020		1.94%
Long-term Debt, Maturities, Repayments of Principal after Year Five	176,161
Thereafter		3.33%
Average rate, total, excluding prepayment penalty	2.30%	2.39%
Long Term Debt Maturities Average Rate In After Year Five	3.16%
Broker Repurchase Agreements
Long-term Debt, Fiscal Year Maturity [Abstract]
2017	300,000
2018		300,000
Total long-term debt, excluding prepayment penalty	300,000	300,000
Prepayment penalty	$ (14,800)
Long-term Debt, Fiscal Year Maturity, Average Rate [Abstract] [Abstract]
2017	1.75%
2018		1.75%
Average rate, total, excluding prepayment penalty	1.75%	1.75%

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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