Related Party Transactions (Narrative) (Details) - USD ($)	3 Months Ended						6 Months Ended		12 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Investment expense	$ 5,400,000				$ 3,549,000		$ 9,353,000	$ 7,343,000
Commissions and fees	524,788,000				547,343,000		1,032,722,000	1,102,633,000
Other invested assets	373,782,000		$ 348,541,000				373,782,000		$ 348,541,000
Net investment income	131,972,000				100,160,000		257,041,000	196,871,000
Fee income from revenue sharing agreement	115,205,000				98,603,000		224,593,000	198,140,000
Contributed capital							0		0
Prudential Insurance
Related Party Transaction [Line Items]
Stock option program plan expense	100,000				0.0		100,000	100,000
Deferred compensation program expense	200,000				100,000		500,000	300,000
Pension plan expense	600,000				500,000		1,100,000	900,000
Welfare plan expense	500,000				500,000		$ 1,100,000	1,100,000
Defined contribution plan employer matching contribution percent							4.00%
Defined contribution plan, cost recognized	300,000				200,000		$ 500,000	400,000
Affiliated Entity
Related Party Transaction [Line Items]
Accrued interest receivable related to long-term notes receivables	100,000		300,000				100,000		300,000
Revenue related to long-term notes receivable	100,000				100,000		200,000	200,000
Interest expense related to loans payable	24,000,000				15,000,000		40,000,000	30,000,000
Affiliated Entity | PAD
Related Party Transaction [Line Items]
Commissions and fees	25,000,000				29,000,000		49,000,000	59,000,000
Affiliated Entity | ASTISI and PGIM Investments
Related Party Transaction [Line Items]
Fee income from revenue sharing agreement	24,000,000				27,000,000		48,000,000	54,000,000
Affiliated Entity | PGIM
Related Party Transaction [Line Items]
Investment expense	4,000,000				3,000,000		8,000,000	6,000,000
Prudential Financial Joint Venture
Related Party Transaction [Line Items]
Other invested assets	294,000,000		228,000,000				294,000,000		$ 228,000,000
Net investment income	4,000,000				2,000,000		9,000,000	2,000,000
Prudential Financial
Related Party Transaction [Line Items]
Company's share of corporate expenses (benefits)	4,000,000				4,000,000		8,000,000	$ 8,000,000
Line of credit facility, maximum borrowing capacity	9,000,000,000						$ 9,000,000,000
PAI
Related Party Transaction [Line Items]
Return of capital	$ 247,000,000	$ 245,000,000	$ 225,000,000	$ 250,000,000	$ 250,000,000	$ 300,000,000