Consolidating financial information by industry segment (Cash Flow Statements) (Details) - USD ($) $ in Thousands		3 Months Ended
		Jun. 30, 2015		Jun. 30, 2014
Cash flow from operating activities:
Net earnings		$ 171,285		$ 124,474
Adjustments to reconcile net earnings to cash provided by operations:
Depreciation		96,966		84,010
Amortization of deferred policy acquisition costs		4,778		4,184
Change in allowance for losses on trade receivables		(61)		22
Change in allowance for inventory reserves		(248)		(1,760)
Net gain on sale of real and personal property		(45,984)		(22,959)
Net (gain) loss on sale of investments		(1,453)		(874)
Deferred income tax		18,866		12,407
Net change in other operating assets and liabilities:
Reinsurance recoverables and trade receivables		(19,349)		(717)
Inventories		(140)		(561)
Prepaid expenses		56,624		5,368
Capitalization of deferred policy acquisition costs		(7,137)		(6,575)
Other assets		10,111		(6,814)
Related party assets		5,666		8,089
Accounts payable and accrued expenses		51,912		94,004
Policy benefits and losses, claims and loss expenses payable		11,669		(9,878)
Other policyholders' funds and liabilities		4,468		1,827
Deferred income		8,342		7,683
Related party liabilities		1,438		1,878
Net cash provided by operating activities		367,753		293,808
Cash flow from investing activities:
Property, plant and equipment		(452,572)		(343,988)
Short term investments		(73,517)		(62,293)
Fixed maturities investments		(47,072)		(69,426)
Equity securities		(967)		(3,281)
Preferred stock		(2)		(2)
Real estate		(23)		(4,211)
Mortgage loans		(82,839)		(5,069)
Proceeds from sale of:
Property, plant and equipment		194,133		128,989
Short term investments		88,332		62,631
Fixed maturities investments		30,340		25,624
Equity securities		$ 799		2,009
Preferred stock				1,000
Mortgage loans		$ 14,306		12,069
Net cash used by investing activities		(329,082)		(255,948)
Cash flow from financing activities:
Borrowings from credit facilities		88,206		207,152
Principal repayments on credit facilities		$ (82,797)		(52,464)
Debt issuance costs				(2,422)
Capital lease payments		$ (33,974)		(18,007)
Leveraged Employee Stock Ownership Plan		929		87
Investment contract deposits		39,252		37,892
Investment contract withdrawals		(13,215)		(11,551)
Net cash provided by (used in) financing activities		(1,599)		160,687
Effects of exchange rate on cash		(3,360)		(1,074)
Increase (decrease) in cash and cash equivalents		33,712		197,473
Cash and cash equivalents at the beginning of period		441,850		495,112
Cash and cash equivalents at the end of the period		475,562		692,585
Operating Segments [Member] | Moving and Storage Consolidations [Member]
Cash flow from operating activities:
Net earnings		171,285		124,474
Earnings from consolidated entities		(6,950)		(5,594)
Adjustments to reconcile net earnings to cash provided by operations:
Depreciation		$ 96,966		$ 84,010
Amortization of deferred policy acquisition costs
Change in allowance for losses on trade receivables		$ (61)		$ 18
Change in allowance for inventory reserves		(248)		(1,760)
Net gain on sale of real and personal property		$ (45,984)		$ (22,959)
Net (gain) loss on sale of investments
Deferred income tax		$ 19,675		$ 10,697
Net change in other operating assets and liabilities:
Reinsurance recoverables and trade receivables		(17,122)		(13,561)
Inventories		(140)		(561)
Prepaid expenses		$ 56,624		$ 5,368
Capitalization of deferred policy acquisition costs
Other assets		$ 9,237		$ (7,487)
Related party assets		5,496		8,855
Accounts payable and accrued expenses		50,325		92,473
Policy benefits and losses, claims and loss expenses payable		$ 6,074		$ 613
Other policyholders' funds and liabilities
Deferred income		$ 8,342		$ 7,683
Related party liabilities		830		1,018
Net cash provided by operating activities		354,349		283,287
Cash flow from investing activities:
Property, plant and equipment		$ (452,572)		$ (343,988)
Short term investments
Fixed maturities investments
Equity securities
Preferred stock
Real estate
Mortgage loans		$ (8,226)		$ (3,719)
Proceeds from sale of:
Property, plant and equipment		$ 194,133		$ 128,989
Short term investments
Fixed maturities investments
Equity securities
Preferred stock
Mortgage loans		$ 1,075		$ 8,154
Net cash used by investing activities		(265,590)		(210,564)
Cash flow from financing activities:
Borrowings from credit facilities		41,206		207,152
Principal repayments on credit facilities		(65,797)		(52,464)
Debt issuance costs				(2,422)
Capital lease payments		(33,974)		(18,007)
Leveraged Employee Stock Ownership Plan		$ 929		$ 87
Investment contract deposits
Investment contract withdrawals
Net cash provided by (used in) financing activities		$ (57,636)		$ 134,346
Effects of exchange rate on cash		(3,360)		(1,074)
Increase (decrease) in cash and cash equivalents		27,763		205,995
Cash and cash equivalents at the beginning of period		431,873		464,710
Cash and cash equivalents at the end of the period		459,636		670,705
Operating Segments [Member] | Property and Casualty Insurance [Member]
Cash flow from operating activities:
Net earnings		$ 4,211	[1]	$ 2,614	[2]
Earnings from consolidated entities
Adjustments to reconcile net earnings to cash provided by operations:
Depreciation
Amortization of deferred policy acquisition costs
Change in allowance for losses on trade receivables
Change in allowance for inventory reserves
Net gain on sale of real and personal property
Net (gain) loss on sale of investments		$ (781)	[1]	$ (127)	[2]
Deferred income tax		1,004	[1]	115	[2]
Net change in other operating assets and liabilities:
Reinsurance recoverables and trade receivables		$ (1,576)	[1]	$ 13,888	[2]
Inventories
Prepaid expenses
Capitalization of deferred policy acquisition costs
Other assets		$ 831	[1]	$ 721	[2]
Related party assets		$ 170	[1]	$ (885)	[2]
Accounts payable and accrued expenses
Policy benefits and losses, claims and loss expenses payable		$ (908)	[1]	$ (14,843)	[2]
Other policyholders' funds and liabilities		$ (425)	[1]	$ 581	[2]
Deferred income
Related party liabilities		$ 146	[1]	$ 668	[2]
Net cash provided by operating activities		$ 2,672	[1]	$ 2,732	[2]
Cash flow from investing activities:
Property, plant and equipment
Short term investments		$ (11,824)	[1]	$ (13,040)	[2]
Fixed maturities investments		$ (9,827)	[1]	(19,217)	[2]
Equity securities				(3,281)	[2]
Preferred stock		$ (2)	[1]	$ (2)	[2]
Real estate		$ (6)	[1]
Mortgage loans				$ (1,350)	[2]
Proceeds from sale of:
Property, plant and equipment
Short term investments		$ 10,298	[1]	$ 20,051	[2]
Fixed maturities investments		$ 6,221	[1]	11,626	[2]
Equity securities				$ 2,009	[2]
Preferred stock	[2]
Mortgage loans		$ 4,064	[1]	$ 243	[2]
Net cash used by investing activities		$ (1,076)	[1]	$ (2,961)	[2]
Cash flow from financing activities:
Borrowings from credit facilities
Principal repayments on credit facilities
Debt issuance costs	[2]
Capital lease payments
Leveraged Employee Stock Ownership Plan
Investment contract deposits
Investment contract withdrawals
Net cash provided by (used in) financing activities
Effects of exchange rate on cash
Increase (decrease) in cash and cash equivalents		$ 1,596	[1]	$ (229)	[2]
Cash and cash equivalents at the beginning of period		8,495	[5]	12,758	[2]
Cash and cash equivalents at the end of the period		10,091	[6]	12,529	[2]
Operating Segments [Member] | Life Insurance [Member]
Cash flow from operating activities:
Net earnings		$ 2,739	[1]	$ 2,980	[2]
Earnings from consolidated entities
Adjustments to reconcile net earnings to cash provided by operations:
Depreciation
Amortization of deferred policy acquisition costs		$ 4,778	[3]	$ 4,184	[4]
Change in allowance for losses on trade receivables				$ 4	[2]
Change in allowance for inventory reserves
Net gain on sale of real and personal property
Net (gain) loss on sale of investments		$ (672)	[1]	$ (747)	[2]
Deferred income tax		(1,813)	[1]	1,595	[2]
Net change in other operating assets and liabilities:
Reinsurance recoverables and trade receivables		$ (651)	[1]	$ (1,044)	[2]
Inventories
Prepaid expenses
Capitalization of deferred policy acquisition costs		$ (7,137)	[1]	$ (6,575)	[2]
Other assets		$ 43	[1]	$ (48)	[2]
Related party assets
Accounts payable and accrued expenses		$ 1,587	[1]	$ 1,531	[2]
Policy benefits and losses, claims and loss expenses payable		6,503	[1]	4,352	[2]
Other policyholders' funds and liabilities		$ 4,893	[1]	$ 1,246	[2]
Deferred income
Related party liabilities		$ 462	[1]	$ 311	[2]
Net cash provided by operating activities		$ 10,732	[1]	$ 7,789	[2]
Cash flow from investing activities:
Property, plant and equipment
Short term investments		$ (61,693)	[1]	$ (49,253)	[2]
Fixed maturities investments		(37,245)	[1]	$ (50,209)	[2]
Equity securities		$ (967)	[1]
Preferred stock
Real estate		$ (17)	[1]	$ (4,211)	[2]
Mortgage loans		$ (74,613)	[1]
Proceeds from sale of:
Property, plant and equipment
Short term investments		$ 78,034	[1]	$ 42,580	[2]
Fixed maturities investments		24,119	[1]	$ 13,998	[2]
Equity securities		799	[1]
Preferred stock	[2]			$ 1,000
Mortgage loans		9,167	[1]	3,672	[2]
Net cash used by investing activities		(62,416)	[1]	$ (42,423)	[2]
Cash flow from financing activities:
Borrowings from credit facilities		47,000	[1]
Principal repayments on credit facilities		$ (17,000)	[1]
Debt issuance costs	[2]
Capital lease payments
Leveraged Employee Stock Ownership Plan
Investment contract deposits		$ 39,252	[1]	$ 37,892	[2]
Investment contract withdrawals		(13,215)	[1]	(11,551)	[2]
Net cash provided by (used in) financing activities		$ 56,037	[1]	$ 26,341	[2]
Effects of exchange rate on cash
Increase (decrease) in cash and cash equivalents		$ 4,353	[1]	$ (8,293)	[2]
Cash and cash equivalents at the beginning of period		1,482	[5]	17,644	[2]
Cash and cash equivalents at the end of the period		5,835	[6]	9,351	[2]
Consolidation, Eliminations [Member]
Cash flow from operating activities:
Net earnings		(6,950)		(5,594)
Earnings from consolidated entities		$ 6,950		$ 5,594
Adjustments to reconcile net earnings to cash provided by operations:
Depreciation
Amortization of deferred policy acquisition costs
Change in allowance for losses on trade receivables
Change in allowance for inventory reserves
Net gain on sale of real and personal property
Net (gain) loss on sale of investments
Deferred income tax
Net change in other operating assets and liabilities:
Reinsurance recoverables and trade receivables
Inventories
Prepaid expenses
Capitalization of deferred policy acquisition costs
Other assets
Related party assets				$ 119	[7]
Accounts payable and accrued expenses
Policy benefits and losses, claims and loss expenses payable
Other policyholders' funds and liabilities
Deferred income
Related party liabilities				$ (119)	[7]
Net cash provided by operating activities
Cash flow from investing activities:
Property, plant and equipment
Short term investments
Fixed maturities investments
Equity securities
Preferred stock
Real estate
Mortgage loans
Proceeds from sale of:
Property, plant and equipment
Short term investments
Fixed maturities investments
Equity securities
Preferred stock
Mortgage loans
Net cash used by investing activities
Cash flow from financing activities:
Borrowings from credit facilities
Principal repayments on credit facilities
Debt issuance costs
Capital lease payments
Leveraged Employee Stock Ownership Plan
Investment contract deposits
Investment contract withdrawals
Net cash provided by (used in) financing activities
Effects of exchange rate on cash
Increase (decrease) in cash and cash equivalents
Cash and cash equivalents at the beginning of period
Cash and cash equivalents at the end of the period

[1] Balance for the period ended March 31, 2015

[2] Balance for the period ended March 31, 2014

[3] Balances for the quarter ended March 31, 2015

[4] Balances for the quarter ended March 31, 2014

[5] Balances as of December 31, 2014

[6] Balances as of March 31, 2015

[7] Eliminate intercompany investments