Fair Value of Financial Instruments - Quantitative Estimates for Level 3 Assets (Details) (Level 3, USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
US Treasury and Government
Fair Value, Option, Quantitative Disclosures [Line Items]
U.S. government and agency	81.1	80.2
US Treasury and Government \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	0.91%	1.02%
US Treasury and Government \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	3.37%	3.64%
US Treasury and Government \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	2.46%	2.75%
State and political subdivision
Fair Value, Option, Quantitative Disclosures [Line Items]
State and political subdivision	88.3	65.9
State and political subdivision \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	2.03%	2.34%
State and political subdivision \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	4.25%	4.50%
State and political subdivision \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	3.01%	3.33%
Corporate
Fair Value, Option, Quantitative Disclosures [Line Items]
Corporate	1,186.4	1,053.3
Corporate \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	0.85%	0.93%
Corporate \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	6.56%	6.88%
Corporate \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	3.06%	3.35%
Other asset-backed (“ABS”)
Fair Value, Option, Quantitative Disclosures [Line Items]
Other ABS	9.6	9.8
Other asset-backed (“ABS”) \| Minimum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	1.61%	1.83%
Other asset-backed (“ABS”) \| Maximum
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	2.60%	3.01%
Other asset-backed (“ABS”) \| Weighted Average
Fair Value, Option, Quantitative Disclosures [Line Items]
Yield	3.80%	2.01%
Fair value investments
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value investments	1.0	1.0
Default rate	0.18%	0.17%
Recovery rate	44.00%	44.00%

PHL VARIABLE INSURANCE CO /CT/ 10-Q